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We've all seen the algorithms for solving Rubik's Cube by hand using a step-by-step approach: get all the corners done, then get the side cubelets done. Or: do a complete side, then do the next one, then the next.

There are several approaches and, by dint of some fairly rigorous practice, experts can solve a cube in under a minute. But how jumbled can a cube get? Or, to put it another way: what's the minimum number of moves necessary? Enter God's Algorithm.

Way back when, I studied mathematics at Kings College, London. Every year, in the summer term, the Mathematical Society organised a weekend away in Windsor Great Park, where we'd invite guest speakers to present topics we wouldn't normally encounter in our regular maths courses.

Gleaning the cube

In 1979, we had Professor David Singmaster as our guest. His topic was a brand-new toy called Rubik's Cube – not yet officially available in England – and the use of combinatorial mathematics to solve it.

The cube had been invented by Erno Rubik in Hungary some five years previously and at that point Ideal Toys were just on the verge of licensing the cube from Rubik for worldwide distribution. Singmaster had a set of cubes with him that we could buy and, needless to say, after his talk he sold the lot.

Within a couple of months, I'd got the art of solving a cube sufficiently practised that I could regularly solve one within a couple of minutes. As we were maths students, we understood the mathematics behind the cube.

The initial solution that Singmaster discovered used combinatorial mathematics to solve it. In essence, he'd devised a set of combined moves (let's call them Moves, each containing about seven to 12 individual face rotations), that would move around three corners or three sides.

All of the Moves were of the form aba' – that is, a set of rotations a, followed by a single rotation b, followed by the reverse set of rotations that formed a.

Instead of hopelessly randomising the cubelets, the Moves were designed to only swap the positions of three cubelets around. By identifying three cubelets that were out of position, you could solve the cube by repeatedly applying these Moves.

I practised two Moves by heart – one to swap three corners, one to swap three side cubelets – until I could do them in my sleep. With my tuned cube, that meant I could solve a random position in about two minutes. That's not a brilliant time to be sure, but acceptable.

Two questions left open at that time were: how randomised could you make the cube, and what would be the optimal number of moves that an omnipotent solver – in other words a solver who could perfectly analyse the cube – would take in order to render the cube to its default state?

Obviously our combinatorial solution would require many moves – possibly 100 – but what about if you could visualise the solution perfectly? 10? 20? 42? This optimal cube analysis became known as God's Algorithm, not because there is such an algorithm necessarily, but because it gives us something to aim for in our ever-better algorithms for solving the cube.

Back in 1982, Singmaster hypothesised that God's Algorithm might only need a number of moves "in the low twenties", but he was unable to refine that hypothesis much further.

The magic cube

Before we can even begin to solve the cube, we need some notation so that we don't drown in descriptive phrases. Even today, we still use the same notation devised by Singmaster back in 1982 in his book Notes on Rubik's Magic Cube.

The Cube consists of three types of cubelets, assembled together with what looks to be utter magic in a 3 x 3 x 3 cube.

There are 12 edge cubelets, each with two faces of different colours.

Similarly, there are eight corner cubelets, each with three visible faces, with each face a different colour. Finally there are six centre cubelets each showing one face.

The centre squares form the sprung matrix that holds it all in place.

These centre pieces define the colour of their sides in the solved state. Hold the cube in front of you, such that there is one side directly facing you. The six sides of the cube are called Front, Back, Left, Right, Up and Down.

We use Up and Down instead of Top and Bottom because we're about to use the initial letters to signify the rotations of their respective face, and to use both Bottom and Back in this case would clash confusingly.

The letters F, B, L, R, U and D denote a clockwise quarter-turn of the respective face. By clockwise we refer to the direction you rotate the face if you were looking directly at it. A half turn of a face is denoted by either repeating the letter (for example, FF or UU) or by squaring the letter (such as B2 or R2).

A quarter-turn anti-clockwise is denoted by using a prime mark or apostrophe (such as D' or L'). Of course, a quarter-turn anticlockwise could be denoted by repeating a letter three times, but this is rarely seen.

Cross wits

As an example, here's how to get the simple crosses pattern from a default cube: L2R2U2D2F 2B2 (or LLRRUU DDFFBB). To return to the solved cube, just reverse the moves.

For the cleverer looking centre dots pattern, try L'R•U'D•B'F•L'R (here I've separated the moves in pairs to make it easier to see what's going on). Again, to return to the pristine cube, just reverse the moves.

Singmaster's original solution was in three main stages: First, choose a colour (I always go for white as it's the most visible) and then restore that particular face. In general, you do this by first restoring the edge cubelets and then the corner cubelets.

CROSS PATTERN: Putting the Cross pattern on the Rubik's Cube can set you up for some quickfire puzzle-solving

Second, restore the middle layer. This of course means making sure the four edge cubelets are properly positioned and in the correct orientation.

Third, restore the final face. Singmaster did this part in four main phases: flipping the edge cubelets so that they all showed the final colour, forming a cross with the centre cubelet (of course, they could be in the wrong position); restore the edge cubelets to their proper position; place the corner cubelets in their proper position (although they may be oriented incorrectly); twist the corners until they are in the correct orientation.

Singmaster's algorithm was guaranteed to solve the cube, but the number of moves was not optimal in any sense of the word. It could take over 100 moves to solve the cube using his algorithm.

Once Singmaster had published his algorithm (a solution that required you to learn six basic Moves and then apply them over and over), the race was on to reduce the number of moves drastically in order to solve the cube more quickly.

Quite soon after Singmaster published his initial book, Jessica Fridrich devised a four-pass algorithm known as CFOP (Cross, First two layers, Orient last layer, Permute last layer) that proved to be extremely fast for the new sport of speedcubing – that is, solving the cube very fast in competitions.

Unfortunately, the algorithm requires the knowledge and use of some 120 Moves, but offset against that a practiced speedcuber can analyse and solve a randomised cube in about 55 rotations.

Picking up speed

Philip Marshall then described an algorithm that only required learning two Moves (plus the art of knowing how to recognise when to apply them), but that would solve the cube in somewhere around 65 moves.

It's a five-step process: Cross, centre section edges, top edges, five corner pieces, end game. Next up was Lars Petrus' method, which he devised at roughly the same time as everyone else in the early '80s.

He decided to avoid the traditional layered approach used by everyone else and to restore the cube from one corner, building it out via a solved 2 x 2 x 2 cube, to a 2 x 2 x 3 rectangular block (otherwise known as a cuboid) to the completed cube.

Although the first few passes use several types of Moves, the final stages of the Petrus System only use three. Overall the cube can be solved in 45 moves, provided that time is available to study the cube in advance.

In speed contests, the number of moves increases somewhat to something in the region of 60 moves because there's less time to study the cube in order to devise the most efficient solution. Apart from some tweaks of these methods over the years, that's where human-solving now stands.

The fastest speedcubers use some variant of these methods. But what about computer solutions? Can they get closer to God's Algorithm through lengthy analyses of the randomised cube?

The first approaches were made by professor Morwen B Thistlethwaite at the same time as Singmaster was explaining his method, and were published in Scientific American in 1981 by Douglas Hofstadter. In essence, Thistlethwaite divided up the solving process into subproblems.

Rather than concentrating on solving portions of the cube and endeavouring to not jumble up those parts as you tried to solve the remainder of the cube, he concentrated on the kinds of moves you were allowed to make. To do this, he made use of group theory and searching by computer.

He started off with what's known as the cube group. This is a mathematical group whose operations are all the usual moves we've discussed here: F, B, L, R, U, D and the moves obtainable from them (F 2, F', B2, B' and so on).

The number of possible positions in this cube group is immense: 4.3 x 1,019. He then posited another smaller group, one that only allowed the following moves: L, R, F, B, U2 and D2 . Next he worked out a set of tables of the Moves that would take the cube from the larger group to the smaller group.

Once in this smaller group, he devised yet another smaller group that only allowed L, R, F 2, B2, U2 and D2, and then worked out how to transform the cube into a member of this group. From there he went to the next more restrictive group that only allowed L2, R2, F2, B2, U2 and D2. From this particular group it was a small search that led to the final and smallest group of all: the identity group (the solved cube).

It is important to note that Thistlethwaite's algorithm requires many searches at each step down the group chain and is only feasible for computers to do, not humans. Using this algorithm, it is possible to solve the cube in a maximum of 52 moves.

Nearing God's algorithm

The final improvement was made by Herbert Kociemba in 1992. He built his algorithm based on Thistlethwaite's by removing most of the interim groups. Kociemba's algorithm just used three groups: the cube group, the U, D, F2, B2, L2 and R2 group, and the identity group.

He called it a two-phase algorithm, because you transform the cube into a member of the smaller group, and then transform that into the only member of the identity group.

The important thing about the U, D, F2, B2, L2 and R2 group is that the orientations of the corners and edges cannot be changed using those particular operations.

Furthermore, the edges in the middle slice between the Up and Down faces stay within that slice. The first phase uses a modified A* search algorithm known as iterative deepening A* (or IDA) in order to find the moves that will constrain the corners and edges (and the middle slice) of the cube to fit into the second group.

The second phase then searches for the moves to solve the cube using only the restricted moves allowed. In fact the algorithm is a little cleverer than it may at first appear: it solves the cube multiple times in order to find the shortest solution path available.

First it uses the shortest path provided by the first search and transforms the resulting cube to the solved state. Then it uses the less successful paths from the original search and tries to transform those to the solved state.

After completing this process, it chooses the shortest path it finds as the solution. In general, it finds a path that is 20 moves or shorter to solve the cube. Note however, that the shortest path it finds is not necessarily guaranteed to be the most optimal solution.

So, Kociemba's Algorithm, although very effective, can only ever approximate God's Algorithm. We're still waiting for that one.

Steve Jobs has launched iOS 4.1 at a press event in California earlier today, while revealing that 6.5 billion apps have been sold to date, with an amazing 200 apps sold every second.

Jobs demonstrated how the HD photo capability of iPhone 4 has been considerably improved with the latest upgrade to iOS.

New game from Epic

Next up, the Apple CEO announced the latest developments in Game Center, introducing Mike Capps, the President of Epic Games to demonstrate the latest developments in Game Center.

Epic demonstrated a game code-named 'Project Sword' - a gorgeous 3D world filled with an impressive amount of detail.

Project Sword will be available this coming Christmas holiday season.

It's a decidedly hardcore gamer's game for the iPhone and will no doubt manage to convert a number of gamers still currently sitting on the fence about mobile gaming.

British manufacturer Novatech has topped a Which? Reliability survey, with the PC maker scoring the same as giants Apple and Compaq.

Novatech, a Portsmouth-based company, was behind Apple in the customer score getting 81 per cent compared to the latter's 94 per cent, but the manufacturer can hold its head up high.

Sarah Kidner, Editor, Which? Computing said: "It's great to see a smaller, home-grown brand beating giants like Dell for both reliability and customer satisfaction."

23 years

Novatech was founded back in 1987, and now employs over 150 people at its head office, with branches in Portishead and Reading.

"Our value is a combined measure of price, quality, performance and service," states the company. "Our aim is to provide our customers with the best value IT products with total customer satisfaction, first time, every time.

"We aim to deliver this by working as one team confidently, helpfully and honestly."

And, according to consumer bible Which?, the company is doing a decent job of it.

Chip giant Intel has purchased the wireless chip division of Germany's Infineon for £900 million.

Infineon is perhaps best known to consumers as the company that makes the chips used by Apple in its iPhones.

The deal follows Intel's £4.9 billion purchase of McAfee earlier this month, the US security software company.

Intel aims for smartphones

Both deals are part and parcel of Intel moving its business away from its traditional core of producing CPUs for personal computers, into newer growth markets such as security and mobile/wireless.

Intel downgraded its sales outlook last week, noting that consumer demand for computers was slowing in what it sees to be a slower-than-expected recovery for the worldwide PC market.

The company reduced its expected third-quarter revenues to $11bn, down from an estimated $11.6bn forecast only six weeks ago.

Intel's latest purchase of Infineon's wireless unit will allow the company to boost its position in the fast-growing smartphone market.

The mobile unit will remain as a standalone business, according to statements issued by both Infineon and Intel.

"Infineon would make Intel an instant heavyweight (in the mobile space) and buy them three, four years in R&D," IDC analyst Flint Pulskamp told Reuters.

The success of Google Labs – the public experimental playground for Google's latest applications – is down to a mixture of peer pressure and public feedback, according to product manager Aparna Chennapragada.

Speaking to TechRadar, Chennapragada explained the process behind Labs, which has been the launching groud for some of the biggest hits for Google, including Google Alerts, Google Reader, Google Suggest and Google Maps.

"Labs is actually intentionally a playground," said Chennapragada who is soon leaving to work on video search within the company. "That was the way we designed it.

"A normal idea can take three years to get to the public, but with Labs we can get them out early – even if they are a little rough around the edges, and by getting them out early we can start to get user input that can help to shape the product."

Dogfooding

Although the public's input is vital to each project, before it arrives on Labs, every idea goes through a stringent peer review process within Google.

"Engineers are encouraged to take their ideas as close to a prototype as they can and it is then shared among the teams to try," she added

"We call this dogfooding – it happens not only for labs products but other products as well – and the barrage of criticism that arrives from the moment it goes out is immensely useful…in retrospect!"

Much of the features applications released through Google Labs comes from the famed '20 per cent' time offered by Google to its engineers, where people are encouraged to work on their own products for one day a week .

Own devices

Chennapragada told TechRadar that the products are not monitored, with even a small success rate still bringing huge dividends for the company.

"The 20 per cent products are not monitored. It's nice to go away and see if an idea works, and actually the hit rate – even if it's one per cent of products – is pretty good.

"It's a nice experimental process that sometimes provides something concrete or sometimes something that becomes a main product if it proves it merits it."

We can always find an excuse to break out the soldering iron and play with a small pile of components.

A project that has been knocking around the internet for a few years is WinLIRC. It enables your PC to receive and transmit infrared signals with the right hardware. That 'right hardware' is something we can easily cobble together with an IR receiver and a few basic components.

Using WinLIRC you're able to monitor the IR signals and control your PC. The main limitation is that WinLIRC only works via a serial port or, alternatively, if your mobo has it through an Irda header.

We're going to first put together a basic serial connection for an IR receiver. Take a trip to the RS Components site at uk.rs-online.com and pick up a 38KHz PNA4602M receiver.

The WinLIRC site offers a list of tested components at www.lirc.org/receivers.html though it's a little outdated. As long as it's a three pin, 38/36KHz unit it should be work with most remotes.

You could connect this directly to the suitable serial port's pins: five for the ground, seven for the 5v power from the RTS line and pin 1 for the Data. However, it's advisable to add a suitable 5v regulator to the power line with the usual resistor, capacitor and a diode to guarantee a regulated supply.

You can actually make the IR receiver wires as long as you require, however we're going for the built-into-the-D-sub-hood effect and will use a 9-pin extension cable to position the receiver.

What you will need

38KHz IR receiver
4.7μF capacitor
1N4148 diode
4.7k Ohm resistor
78L05, 100mA, 5v regulator (TO-92 casing)
9-pin SUB-D socket and hood

How to make a detector

1. What could we turn this pile of components into? Let's find out...

2. This is the schematic, you can read this right? Oh, okay lets show you how to make this.

3. The plan is to cram everything into the D-sub case, it'll have to be organised a little like this.

4. To start, snip the right sides of the resistor, diode and capacitor to around 10mm. Solder the resistor to pin 1, capacitor to pin 5 and the negative diode leg to pin 7. This all fits into the thick end of the hood.

5. Take the voltage regulator and identify the In, GND and Out connections each type can be different. Solder the middle GND to pin 5. Solder the 'in' to both the outputs of the diode and resistor. Solder the 'out' to the other capacitor's connection.

6. Take two short runs of wire and solder these to pins 1 and 5.

7. Solder the Data leg of the IR receiver to the pin-1 wire and the GND to the pin-5 wire.

8. Finally, solder the middle Vcc leg of the IR receiver to the output of the voltage regulator and capacitor. Gently bend the components into place and it should all fit.

9. The WinLIRC software will need to be configured for the correct COM port. You can click the 'RAW' button to view IR codes as they're received. Use the 'Learn' button to 'teach' WinLIRC the codes for a specific remote and assign buttons.

10. Check the bottom of winlirc. sourceforge.net page for a list of software that supports WinLIRC. The likes of Media Player Classic and BSPlayer do, snoop around the Options > Keys controls to enable the WinLIRC control.

Security vendor Trend says that Intel's proposed purchase of McAfee is "a clear statement to the industry and investors that security is absolutely fundamental to future technology services and products".

In a statement sent to TechRadar, Trend CEO Eva Chen went onto say that Intel would use its vast resources to upsell McAfee security protection to purchasers of other Intel products and services.

"For current and future customers, Intel's resources may now enable McAfee to offer protection to multiple devices and endpoints, replicating what other vendors, such as Trend Micro, have already achieved through the Smart Protection Network.

Embedded software model

"However," says Chen, "the embedded-software model is fundamentally different from the security-software operating model and this is a good opportunity for customers to review their relationship with their security partner to assess whether they will be receiving the services and expertise they need."

If the deal goes through, McAfee will become a wholly owned but separate subsidiary of Intel costing in the region of $7.7 billion. McAfee will report into Intel's Software and Services Group.

In a phone conference yesterday, Intel CEO Paul Otellini said that the proposed acquisition of McAfee will enable Intel to innovate across all three key pillars of computing. "We have concluded that security has become the third pillar of computing after energy efficient performance and internet connectivity," he said.

McAfee is the world's largest dedicated security technology company with 6,100 employees based in Santa Clara.

Intel CEO Paul Otellini says that the proposed acquisition of security giant McAfee will enable Intel to innovate across all three key pillars of computing.

"Over the past couple of decades there have been a few critically important inflexions in computing [such as the internet and rise of the personal computer] and we now live in a world of multiple devices," said Otellini during a conference call to announce the McAfee deal.

"Growing alongside [this] is the frequency of security attacks. The number of new threats continues to rise," he added.

"As a result, we have concluded that security has become the third pillar of computing after energy efficient performance and internet connectivity." Hence the decision to purchase McAfee.

"We believe this [acquisition] will better protect devices for our users. It allows Intel to innovate over all three pillars of computing."

"The addition of McAfee products and technologies into the Intel computing portfolio brings us incredibly talented people with a track record of delivering security innovations, products and services that the industry and consumers trust to make connecting to the internet safer and more secure," Otellini stated.

Intel says the acquisition "enables a combination of security software and hardware from one company to ultimately better protect consumers, corporations and governments as billions of devices - and the server and cloud networks that manage them - go online".

If it goes through, McAfee will become a wholly owned but separate subsidiary of Intel costing in the region of $7.7 billion. McAfee will report into Intel's Software and Services Group.

Both boards of directors have unanimously approved the deal, which is expected to close after McAfee shareholder approval, regulatory clearances and other customary conditions have been met.

McAfee is the world's largest dedicated security technology company with 6,100 employees based in Santa Clara.

Dell's shareholders are apparently unhappy with the performance of chief exec Michael Dell, with a quarter of them withholding support for the company's founder.

Around 378 million of a total of 1.5 billion votes from Dell shareholders revealed an opposition to Michael Dell's continued presence on Dell's board of directors, it was revealed in a regulatory filing made public this week.

Michael Dell owns 11.7 per cent of Dell's outstanding shares.

An iconic figure

Standford Law Professor Joseph A Grundfest, told The New York Times: "Mr. Dell is quite properly an iconic figure at the company.

"It is extremely rare to have that amount of shareholder disaffection directed toward an executive who is so central to the company's past, present and future."

Dell recently paid $100 million to settle up charges of accounting fraud from the US Securities and Exchange Commission, with $4 million of that coming out of Michael Dell's own pocket.

Dell was accused of misleading investors by not disclosing the amount of money it was being paid by Intel in order to bump up the bottom line and meet its quarterly financial targets.

Dell spokesman David Frink defended his chief exec, saying: "Our board of directors has previously reaffirmed its confidence in Mr Dell's leadership and a majority of shareholders agreed."

Microsoft has announced an update for its Windows Live Essentials 2011 Beta, bringing updates like Facebook chat to messenger, video chat, facial recognition and integration with Office.

Microsoft states that it has had 3 million unique users for the beta version of Messenger alone, and the feedback has helped shape the changes to the software - aka Wave 4 beta.

"First, we want to say thank you for your help, blogged Microsoft's Chris Jones.

"For Messenger alone, we had over 3 million unique users, 3.5 million updates to display pictures, 6.2 million video calls, and 7.6 million updates to status messages.

"Your beta feedback and usage has helped shape the many improvements we've made and continue to make across Messenger, Photo Gallery, Movie Maker, Writer, Mail, and Family Safety."

Facebook chat

One of the key additions is integration of Facebook chat into messenger - with a huge overlap between users of the social network and Microsoft's online applications.

"Many of you have been asking for Facebook chat, and it's finally here," adds Jones.

" More than half of all Messenger customers also use Facebook. With the new Facebook chat integration, you now...have one place to chat with all your friends.

"And if you use Facebook but don't use Messenger today, you now have an always-on "people app" on your PC that gives you instant access and notifications as people come online in Facebook or Messenger."

Other improvements listed by Microsoft are:

A quicker Messenger – The time it takes to sign in, and to refresh contacts and social feeds, as well as animation speed, are all faster than in previous versions of Messenger.

More efficient video chat - Messenger video chat uses 30% fewer CPU resources by offloading work to the GPU.

Better facial recognition - Photo Gallery facial recognition is improved significantly and works more quickly.

Larger movie uploads - Movie Maker will upload higher resolution movies to SkyDrive (480x640 vs. the previous 320x480).

Higher bit-rate movies - Movie Maker now supports higher quality (bit-rate) content.

Better spell-checking - Writer has significantly improved the quality of its spell-checking.

Better integration with Office - Writer is much better at retaining all formatting when you copy and paste from Word and other Microsoft Office programs.

Better handling of Gmail – Mail now automatically handles Gmail's spam and trash folders properly.

Faster web filtering - Family Safety web filtering is 35% faster than in the previous version.

The average Windows PC is permanently busy, constantly juggling system resources between the 50 or more processes it's running at any one time.

Sometimes, for no apparent reason, a rogue application will demand all your processor's attention, and before you know it the process is running your processor at 100% all of the time.

This will feel like a major disaster, especially if you've unsaved work in other applications. They will be very unresponsive, it'll be difficult to switch to them, and even if you manage it then little will seem to happen. Just redrawing the screen may take an age. So your first step should be to try and regain control over your system, reducing the impact of the resource-hogging app and allowing access to other programs again.

CHECK TASKS: Task Manager will quickly highlight the resource-grabbing application

Press Ctrl+Shift+Esc to launch Task Manager, then, click the Processes tab and choose "Show processes from all users". You should now see everything running on your PC at the moment. Then click the CPU column header to sort by CPU usage, and look for the process that's the most demanding. (No CPU column? Click View > Select Columns, check the "CPU Usage" box and click OK.)

Once you've discovered the offending process, right-click it and select Set Priority > Low. This tells Windows that just about everything else you're running is more deserving of CPU attention, and may make a very small difference in system responsiveness.

Now right-click the process again, select Set Affinity, and clear all but one of the CPU boxes. The "Processor Affinity" setting tells Windows which CPU cores are allowed to run a particular application, and so by restricting it to one you'll free up the others for the rest of your programs.

BRING IT ROUND: Blocking your rogue process from all but one CPU will quickly bring it into line

The results should be visible immediately, with CPU usage dropping and other programs becoming usable again. Switch to any applications that contain unsaved work, or that you need to be sure are closed properly (your email client, say), save any documents and close them down. And then close everything else non-essential, to simplify your system: all running applications, any system tray icons that are surplus to requirements, the lot.

Malware hunt

One common cause of high CPU utilisation is a malware infection, and so it's important to rule that out first. Run a full system scan with your antivirus package, right now, to see what it turns up. (You don't have one? Download something like AVG Free [free.avg.com] - this isn't going away on its own.)

Your antivirus tool may give you a clean bill of health, but be careful - you can't trust this entirely. It could be that you've been infected by something brand new. This happened to us recently, an instance of svchost.exe began using way too much CPU time, our antivirus package found nothing but we uncovered the malware ourselves. And you may be able to do the same.

To assist in your malware hunting, download and install a copy of Process Hacker [processhacker.sourceforge.net]. Launch the program and you'll see it's basically a more powerful version of Task Manager. Locate the process that's using all your CPU time, and make a note of its Process ID (PID).

HEAVY LOAD: Process Manager provides in-depth data about everything running on your PC

Now click the Network tab, which shows all the network and internet connections that may be open right now. Pay particular attention to any with an entry in the Remote Address column that looks like an internet address (that is, not something local like "127.0.0.1"). If you find your buggy process has a connection open to an address that you don't recognise, and you're not sure why, then that could mean it's malware.

Switch back to the Processes tab, double-click the dubious process and click the Memory tab. Now click String Scan, and Process Hacker will scan every byte of the processes' RAM, looking for text strings: web addresses, file names, messages, whatever they might be. Scroll down the list of everything it finds, looking for anything suspicious. We can't tell you exactly what this might be, but in the case of our svchost.exe infection, for instance, we found a URL something like "www.site.ru/newbot.php": fairly conclusive evidence that we'd been hit by a brand new specimen of malware.

FIND MALWARE: Process Hacker can search a process's RAM, helping to identify malware

If, at the end of this, you also find signs of malware, then you've probably found the cause of your "CPU 100% problem". And the priority is to get it cleaned up.

Try your antivirus package again in a day or two, when maybe an update will help to recognise it, or perhaps download the trial versions of some other packages (though don't install more than one at a time). And in the meantime, treat this PC as compromised: disconnect it from the web, and don't use it to access banking sites or do anything else faintly sensitive.

If there's no hint of viruses or bots, though, you'll need to look elsewhere. And there are plenty of routes you might take.

Bug fixes

If your process problems are the result of a bug, then someone has almost certainly experienced, and probably solved it before. Head off to Google, enter your process name, and keywords like CPU 100, just to see what comes up. And check Device Manager and the Windows Event Viewer for errors that might reveal an underlying issue.

It's also a good idea to identify the author of your troublesome process, too, if you've not done so already. If you discover it belongs to a particular application you've installed, visit the author's website looking for answers, or perhaps try uninstalling, reinstalling or updating the program. Or, if it's a Windows component, try searching at support.microsoft.com.

If none of this produces an answer then Process Hacker may again be able to help. The next time the process goes rogue, reduce its priority and affinity settings, as we recommended earlier, then launch Process Hacker, and locate and double-click the errant application for a closer look.

Click the Threads tab. This shows you every thread the program has open, everything that's actually running some code, along with the number of CPU cycles they're using. Look at the most active threads, then check the "Start Address" to see what they're doing. Now this area of Process Hacker is aimed at programmers, so there are no concessions to ease of use here, but as long as you know the basic rules then you may still be able to extract some useful information.

DRIVER PROBLEMS: Could your 100% CPU issue be caused by a buggy driver? DriverEasy will help you find updates

An Outlook thread start address might look like this, for instance: "iTunesOutlookAddIn.dll!DllUnregisterServer+0x1a6c2". The first part of this address, everything up to the !, tells us the file containing the code that the thread is running. The name here very obviously tells us where it's come from, so if this thread were causing problems then we might disable the addin, or uninstall iTunes. But if you don't recognise the file name, Google it for more information.

And the second part of the address, everything between ! and +, tells us the function that the thread is calling. This is generally more technical, less useful, but may at least give you some clues: if the function name seems related to printing, for instance, then you might go looking at your printer driver and print-related Windows services.

If the very best that Google and Process Hacker have to offer still tell you nothing,though, the best you can do is resort to some more generic solutions.

Update your drivers, for example - a tool like DriverEasy will help identify available upgrades.

You might try updating Windows and your applications, too. Check Windows Update for optional updates it recommends for your PC.

Then simplify your system by ruthlessly uninstalling anything you don't need. Use UpdateStar to highlight available updates for everything else. And if all else fails, reinstalling Windows should at least fix Windows components, freeing up your valuable CPU time and getting your PC back to normal.

Oracle Corporation is suing Google, claiming that the search giant has infringed a number of its copyrights with its Android smartphone operating system.

Oracle filed the lawsuit in a California federal court earlier this month, with Oracle spokeswoman Karen Tillman claiming that, in developing Android, Google "knowingly, directly and repeatedly infringed Oracle's Java-related intellectual property."

Tilman added: "this lawsuit seeks appropriate remedies."

Open source confusions

Google's Android operating system uses portions of Java technology, which is supposedly an open-source platform, with the source code available for free to any developer. Google developed its own Java virtual machine for Android.

Oracle purchased Java developers Sun Microsystems earlier this year in a $5.6 billion deal.

"Sun's corporate philosophy was very different from Oracle's in terms of enforcing the Java patents," IP litigator Edward Reines told Reuters.

Google CEO Eric Schmidt previously headed up Java's development when he was CTO at Sun Microsystems in the 1980s and '90s.

Baseless lawsuit?

"We are disappointed Oracle has chosen to attack both Google and the open-source Java community with this baseless lawsuit," Google spokesman Aaron Zamost said in a statement.

"The open-source Java community goes beyond any one corporation and works every day to make the web a better place."

Mark Driver, an industry analyst at Gartner summed up the case, noting: "Oracle is damned if they do and damned if they don't, so it figured it might as well do and try to get paid.

"There's just tons and tons of potential money in this. But it's bad news for Java regardless of the outcome."

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Hewlett Packard boss Mark Hurd resigned his post at the helm of the world's largest PC company this month following a sexual harassment investigation.

The HP investigation followed allegations from a former contractor with whom Mr Hurd had admitted to having "a close personal relationship" with and had submitted false expense reports over, in order to conceal the nature of the relationship.

Profound lack of judgement

Michael Holston, HP's general counsel, told Bloombergthat Hurd had "demonstrated a profound lack of judgment", but that he had not breached HP's sexual harassment policy.

Mr Hurd himself added: "As the investigation progressed, I realised there were instances in which I did not live up to the standards and principles of trust, respect and integrity that I have espoused at HP."

He is to be replaced on an interim basis by Cathie Lesjak, HP's Chief Financial Officer.

The contractor whose sexual harassment accusation against Hurd has since stepped forward to claim that she was "surprised and saddened" and never intended for Hurd to lose his job.

Accuser steps forward

Former adult movie actress, Jodie Fisher, said via a statement released by her attorney:

"I was surprised and saddened that Mark Hurd lost his job over this. That was never my intention.

"At HP, I was under contract to work at high-level customer and executive summit events held around the country and abroad," Fisher added. "I prepared for those events, worked very hard and enjoyed working for HP."

Fisher worked as a contractor for HP from late 2007 through 2009. Mr. Hurd has since settled the matter privately with Ms. Fisher for an undisclosed sum.

Some people view the digital revolution as being just a little over 50 years old – but the fact is, today's most powerful computers are the result of decades, centuries and even millennia of development.

At the beginning of the story, you could argue, we humans counted with our fingers, and from that clumsy process the Intel Core i7 was eventually born.

To explore the genesis of the computer we set ourselves a task. We wanted to warp back to the very earliest days of computing and track our way through to today. As we walked through the ages, we wanted to identify the most influential computers – machines that shifted the course of computing forever. So, come with us as we visit the most influential computers ever made.

1. The abacus

OK, so the abacus was hardly a computer, but we really can't start our journey anywhere else but here. This ancestor of all mechanised computing aids was first used in Samaria and dates back to before 2,000 BC. A variant is still in use in the Far East today.

In its usual form, the abacus has several rods – each of which represents a power of 10 – onto which beads are threaded so that they're free to slide up and down. If you want to get a hands-on view of how this mechanism assists people with simple arithmetic, take a look at the JavaScript abacus.

While all fell short of what we'd now consider a computer, various arithmetic devices were introduced over the next the two millennia, some of which remained with us until the 20th century.

One abacus descendant is the slide rule. This was an analogue calculating device based on logarithms, and it was famously used by a bunch of boffins in the 1950 BBC election broadcast to calculate the swing as each result came in.

The mechanical adding machine, on the other hand, was a common piece of office equipment until it was replaced by the electronic calculator in the 1970s.

2. Babbage's Difference Engine

An abacus, a slide rule or an adding machine could each be used to perform a single calculation. Babbage's Difference Engine was quite different. It was intended to perform a series of calculations.

Designed between 1847 and 1849, it was never actually built in Babbage's lifetime. In 1991, however, the London Science Museum built a model to Babbage's original plans. It worked perfectly.

Although it was a purely mechanical machine, driven by a crank handle and containing cogs, gears and levers, it accurately calculated and printed tables of polynomials that were used for astronomy and ballistics.

Next came Babbage's steampowered Analytical Engine. Unlike the Difference Engine, which was designed to perform a particular type of computation, the Analytical Engine was a programmable or universal computer in just the same way as today's PCs. Indeed, programs written for it by Babbage's contemporary Ada Lovelace bear an uncanny similarity to modern computer programs.

Add all this up and you could argue that the Analytic Engine represents a more significant step than the Difference Engine did. The problem was that the Analytic Engine was never built by anybody, and so the machine remains largely untested.

3. Colossus

The first completely electronic computer Like Babbage's Analytical Engine (which is best described as a calculating machine), Colossus was a proper computer, albeit one that was designed to perform one very specific type of calculation.

Where it broke new ground was that, for the first time, it was purely electronic. Created by Tommy Flowers and his team at the Post Office Research Station in 1944, it was used at Bletchley Park as part of the World War II code-breaking effort.

While a mechanical computer called the Bombe had been adequate to crack messages encrypted using the famous Enigma machine, the more complicated German Lorenz cipher machine that was used to encode teleprinter traffic required the increased speed of an electronic computer in order to break the code.

Colossus contained no less than 2,400 valves. With memory being expensive, the data was operated on directly from paper tape. As a result, the speed of the computer depended on the speed of the tape reader.

Operating at 40 feet per second (27.3mph), Colossus had a speed of 5,000 characters per second. A rebuilt Colossus is now on show at the National Museum of Computing at Bletchley Park.

4. ENIAC

Designed and built at the University of Pennsylvania under a US government contract, and intended for nuclear weapons research, ENIAC became the world's first 'universal' electronic computer: in other words, one designed to do any job according to its programming.

It was completed in 1946, and its headline figures are startling. It contained 17,468 valves, 7,200 diodes, 1,500 relays, 70,000 resistors, and 10,000 capacitors, all held together by about five million hand-soldered joints. It weighed 27 tonnes, measured 2.6m x 0.9m x 26m, and consumed 150kW of electrical power. When translated into today's terms, it set Uncle Sam back about $6million – and that's not including the power bill!

Despite being the first universal computer, ENIAC differed in several important respects from its various successors. For a start, it operated on decimal rather than binary arithmetic, something that contributed massively to the valve count – which was huge, given its rather pedestrian performance.

More significantly, despite being universal in nature, ENIAC was programmed by plugging patch leads and configuring switches. As a result, changing the machine's configuration from one operation to another was a task that would typically take several days to complete – a far cry from the simple speed of loading a program from disk that we're used to today.

5. The Manchester Baby

The Small Scale Experimental Machine (SSEM), or Manchester Baby, was completed in 1948. It was dubbed Baby in an effort to differentiate the machine from its successor, the Manchester MK1.

The SSEM was groundbreaking. Here was a computer that was fully electronic, truly universal and, for the first time, could execute a program stored in internal memory. As it was the first ever stored program computer, we are able to draw some direct comparisons between the Manchester Baby and today's PCs.

It had 550 valves (transistors, integrated circuits and microprocessors were still some way off), and just seven instructions, which could be executed at a rate of 700 per second. It had 32 words of 32-bit memory.

Although you'd have to put several zeroes on the end of these figures to come close to describing today's PCs, it's fair to say that the world owes a debt of gratitude to SSEM's creators Freddie Williams and Tom Kilburn of the University of Manchester.

6. IBM System/360

Even by the early '60s, a dozen years after the pioneering SSEM, computers were still most definitely for the few rather than the many. IBM, which had entered the computer market back in 1953, was about to change all that.

The IBM System/360 was launched in 1964, and is considered by some to have been the most successful mainframe computer of all time. The System/360 had a 32-bit architecture, something that didn't make its appearance in the PC market for another 21 years. Although few companies could afford to fully populate them, some models could take up to 4MB of memory.

Perhaps the main attraction was that software developed for any model would run on any other, thereby permitting an upgrade path.

IBM soon emerged as head and shoulders above the competition, and went on to dominate the mainframe market for decades. Viewed in the light of today's computers, a System/360 would appear huge. Each component – the CPU, the disk drives, several tape drives, line printers and an operator's console – was housed in its own cabinet, which meant that a system would occupy a whole room, which would need to be both fairly large and well air-conditioned.

7. DEC PDP-8

Despite the success of the IBM System/360, mainframe computers still remained the sole domain of moneyed government departments, universities and large corporations. Generally leased rather than bought, these machines could set their owners back a million dollars a year.

The computers would also need a team of operators to care for the machines, further pushing up costs. By the early 1960s, the race was on to downsize the computer and, in so doing, make computing accessible to smaller organisations.

While other companies may have created mini-computers first, the first firm to really break into this embryonic market was Digital Equipment Corporation (DEC). Introduced in 1965, DEC's PDP-8 was the first mini-computer to sell in significant numbers. It was sold for a fraction of the price of even the smallest IBM System/360 mainframe.

The CPU was about the size of one of today's large PCs, and when the storage and other peripherals were added, the whole computer was about the size of a domestic fridge. Most importantly, it could be operated by the people who needed to use it. It never sold as many as its successor – the hugely popular PDP-11, which was launched in 1970 – but that doesn't change the fact that the PDP-8 got there first.

8. IBM PC

Such was the magnificence of the PDP-8 and the mini-computer era it pioneered that it took a whole 16 years for the next true hero of computing to come along. There were some noteworthy efforts in the interim – the Apple II and the Commodore PET – but they were all overshadowed by the IBM 5150.

This pioneering machine was launched in 1981 and it kick-started the desktop PC revolution. Indeed, your desktop PC of today is very much its direct descendant.

At the time, commercial success wasn't exactly assured, because the 5150 was massively expensive. The original 1981 PC sold for $1,565, which would be the equivalent of $3,900 (or £2,600) today!

Despite these wallet-wilting features, the machine had a very sparse specification. For example, it didn't come with a monitor: you had to use a TV. It had 16kB of memory and, as hard drives were squarely a thing of the future, you had to make do with floppy drives. Even these were an optional extra – IBM intended 5150 machines to store data on cassette tapes.

9. Sinclair ZX81

If imitation is the sincerest form of flattery then IBM must have been over the moon at the appearance of the many clones of its PC that soon flooded the market. Although the following wave of lookalikes succeeded in forcing prices down, back in the 1980s the PC was still most definitely a tool for businesses only.

The machine that changed all that, at least here in the UK, was the Sinclair ZX81, which is still remembered for its super low price. On its launch it took the country by storm. It might have looked more like an overgrown calculator with its primitive membrane keyboard, but it cost just £69.95 (or £49.95 if you were prepared to solder the components onto the circuit board yourself).

Sinclair managed to keep the ZX81's price low by reducing the number of chips on the motherboard from 21 on the ZX80 to four on the ZX81.

Needless to say, the ZX81 didn't pack the same sort of punch as the IBM PC. It had an 8-bit Z80 processor with a clock speed of 3.25MHz, 1kB of RAM, and featured monochrome output to a TV set. The display comprised 24 lines of text, each 32 characters long or, in block graphics mode, it provided a resolution of 64 x 48 pixels. Oh, and you had to use a cassette recorder for storage.

10. Apple Mac

The computer that brought us a GUI and mouse No, you haven't opened a copy of MacFormat by accident: even a dyed-in-the-wool PC user would have to admit that the Apple Macintosh was groundbreaking when it first appeared back in 1984.

Today its all-in-one appearance looks somewhat quaint, but it had one very important thing going for it that wouldn't emerge into the PC world for another eight years. When PCs were still driven by entering cryptic commands at a prompt on a text display, Apple Mac users were clicking graphical icons on-screen and having information presented to them in windows.

Here was the first mass-produced computer to be shipped, as standard, with a graphical user interface and a mouse – and the computer industry has never looked back. While touchscreens and voice input have been hyped as the next breakthrough in user interfaces, this concept is alive and well over a quarter of a century on.

The future of TV is personalised, says Philips. Aprico is a system developed by the Dutch tech giant's technology venture arm that automatically locates and filters relevant TV content. We were shown how the system works at a briefing led by Thomas Dvorak, Aprico's chief marketing officer.

Once the system has learned at least some of your preferences it can immediately begin to build up a personalised channel based on your preferences.

"It automatically records relevant shows," explains Dvorak as he scrolls down a list of readily available content. The system can begin to build the channel based on a single programme selection, which it can then improve as you watch more shows and digest more content – perhaps in terms of online video which, as Dvorak points out, isn't the best experience through a TV.

CREATE A CHANNEL: It's easy to create a channel for whatever content you choose - even while you're watching other content

Crucially though, video on demand (VoD) services can also be incorporated, providing new ways for broadcasters to put premium paid-for content in front of those who are most interested in it via a recommendation engine.

Aprico says that with just 17 days of use, accurate personalised profiles can be created for each user.

Ready-made channels are already available - while content providers could also seed these – and you can also create a channel from a search term, such as a director's name, for example.

Windows Media Center app

The first public-facing venture from Aprico is called Watchmi, and is a German plug-in for Windows Media Center that brings Aprico's personalisation to the desktop. Dvorak hopes that the technology will be implemented in set-top boxes or even TVs themselves in the near future.

Unlike Philips' UWand sytem, there are no special controls; Dvorak shows us the system using a standard Windows Media Center remote through which you access a scrolling EPG.

Dvorak says that a key point of the system is to "provide new revenue streams and [better] targeted advertising".

Aprico's own publicity material calls the system a "next-generation advertising platform" and, while it's clear that Aprico is designed to bring broadcast-level advertising to consumers who are keen to channel hop, Dvorak says there's nothing to stop people skipping through ads. He also says that advertisers will only be charged if adverts are watched, though we can't see many advertisers standing for the ability for their ads to be fast-forwarded through.

FULL EPG: Aprico works like any other EPG, except that it will take note of everything you watch - or everything you skip through

Aprico says that content providers can win too, by providing a more personalised and differentiated service for consumers. Those who implement the technology inside set-top boxes (for example) will also be able to introduce extra interactive content depending on their personal preference.

As the system is software based at the consumer end, device manufacturers and broadcasters will be able to use existing kit should they wish.

The personalised TV service will provide even more options for advertising in the future. Instead of just advertising spots and banners, Watchmi allows them to run personalised videos and short films that are tailored to the user's channel profile, which will allow them to reach their target groups in an optimal manner.

It's that time of year when the quarterly financial results are revealed and latest to step up to the plate is Microsoft, reporting a record financial quarter with earnings in excess of $16 billion (£10.46 billion) for the quarter that ended on June 30 this year.

Microsoft's quarterly revenue was up 22 per cent on the same quarter last year and its yearly revenue of $62.48 billion was up 7 per cent on last year, both record financial results for the company.

Emerging market's growth

The company has sold 175 million Windows 7 licenses to date, with seven per cent more OS licenses sold than PCs, which means that plenty of people with older machines running XP or Vista have chosen to upgrade their OS instead of investing in a new PC.

Microsoft also noted that emerging markets such as India and China are largely responsible for the boost in Windows's 7's growth over the last year.

The Xbox division has continued to perform well, with over 1.5 million games consoles sold throughout the quarter and Xbox Live subscribers now totally over 25 million worldwide.

Transitioning to the cloud

"This quarter's record revenue reflects the breadth of our offerings and our continued product momentum," said Peter Klein, chief financial officer. "The revenue growth, combined with our ongoing cost discipline, helped us achieve another quarter of margin expansion."

"We saw strong sales execution across all of our businesses, particularly in the enterprise with Windows 7 and Office 2010," said Kevin Turner, chief operating officer.

"Our transition to cloud services is well underway with offerings like Windows Azure and our Business Productivity Online Services, and we look forward to continuing our product momentum this fall with the upcoming launches of Windows Phone 7 and Xbox Kinect."

Via Microsoft

The Hewlett Packard slate PC has been listed on the company's website, with the company also applying to trademark the term "PalmPad" – fuelling speculation about the company's plans to introduce what many were referring to earlier this year as a potential 'iPad killer' tablet PC.

The latest details on the HP Slate, from a listing on the HP website, claims that it will feature an 8.9-inch screen, two cameras and run on Windows 7.

Win 7 or Palm WebOS?

HP, the world's largest PC maker, originally announced its plans to release the HP Slate running on Windows 7 OS earlier in 2010.

Since that time, HP has acquired Palm, and is looking to develop Palm's WebOS mobile operating system for a range of new devices, including tablet PCs.

HP has listed the one model of the HP Slate 500 on its website. The device includes an 8.9-inch touchscreen and runs on Windows 7 Premium. The device also has two cameras -- one video and one still -- for users to do "web conferencing," according to the listing.

The HP Slate 500 is described as follows:

"No matter where you are or what kind of fun you're in the mood for, the HP Slate 500 is all you need. Exclusive HP software gives you access to photos, videos and everything on the Internet with just a touch, while Windows 7 Premium gives you the power to do what you want.

"The unique design and 22.6 cm (8.9") screen put the full Internet in your hands, while two cameras (video and still) let you capture life as it happens or participate in web conferencing.

Adjust the screen orientation to fit your content and use the pen to write or draw as if on a piece of paper. Whatever you want to do, the HP Slate 500 helps you do it – and makes it more fun too."

You can see the HP Slate listed in multiple models on this page from HP's website archived on Google.

TechRadar has contacted HP's UK office for further comment.

A tablet computer by Lenovo called LePad should be with us by the end of the year, with the Chinese company taking on Apple with an Android-toting device.

Tablets are likely to be appearing in droves over the next six to nine months, following the success of Apple's iPad, and Lenovo has already impressed with a hybrid tablet/notebook shown off at CES 2010.

The Lenovo U1 featured both an independent touchpad screen and a keyboard, and utilised a Snapdragon processor.

LePad

PCWorld.com stated that the arrival of LePad was confirmed by Liu Jun, senior VP at Lenovo and also confirmed by the company.

The tablet will run Android, possibly the Gingerbread version of the mobile OS that has been built with larger touchscreen devices in mind.

Lenovo has become an increasingly important player in the mobile PC market since buying IBM's PC division and utilising the ThinkPad brand.

Acer has this week announced its new S1 Series LCD displays, ranging from 18.5 inches to 23 inches and measuring a tiny 13mm to 15mm thick.

The four new models offer up full HD, a contrast ratio of 12,000,000:1 and a 5ms response time, as well as packing an attractive, glossy black design.

"Designed from scratch to combine an eye-catching design with excellent video graphic performance, this series is a real jewel, including innovative display technologies to deliver crisp and clear images," the says Acer about the products.

"With clean lines, a polished black bezel and graceful glossy foot stand, the S1 series is the perfect blend of ultra slim, sophistication and style."

Keeping it green

Keeping to its green credentials, Acer continues its EcoDisplay campaign with a logo on the display indicating low environmental impact, made possible by using environmentally friendly materials and achieving low power consumption.

The S1 displays include VGA and DVI ports with HDCP encryption, so you'll be able to watch all of your purchased HD content with their tedious DRM protection. An HDMI port is available on the 21 and 23 inch models only.

That contrast ratio is constantly altered with every frame by Acer's Adaptive Contrast Management to achieve ultra-sharp images.

The Acer S1 Series displays retail from £119.99 for the 18.5inch model, up to £169.99 for the 23 inch.