Whether you're running a small business and don't have a dedicated IT support team, or are a home user without the time or patience to tweak your PC to ensure it runs smoothly, optimisation applications can seem incredibly attractive.

In theory, these pieces of software will locate missing Registry entries, delete temporary and unwanted files, and generally give everything a spruce up.

However, in practice they can negatively affect performance by running in the background and loading at start-up, so there appears to be a fine line between optimisation and diminution.

Of course, tuning software becomes something of an irrelevance if you've bought an SSD, which accelerates Windows far beyond what's achievable by merely tidying the Registry or buying more RAM. But in some cases this isn't practical or affordable.

With this in mind, we've tested eight of the most popular pieces of PC optimisation software. We made a clone of a standard Windows installation with plenty of programs installed, and performed a series of tests to see what difference each piece of software made.

We ran a series of practical and theoretical benchmarks, like timing how long it took to load programs and games using a stopwatch and the ever-useful Apptimer. We also ran Futuremark's browser benchmark Peacekeeper to evaluate the impact the tuning software had on browsing.

Products tested

TuneUp Utilities 2012 - £14
www.pxsoftware.com

Magix PC Check & Tuning - £26
www.magix.com/uk

Ashampoo Winoptimizer 9 - £24
www.ashampoo.com

Norton Utilities - £20
www.symantec.com

Fix-It Utilities 12 - £27
www.avanquest.com

Advanced System Optimizer 3 - $40
www.systweak.com

Iolo System Mechanic 10.7 - $40
www.iolo.com

Piriform CCleaner - Free
www.piriform.com

1. Free TuneUp Utilities 2012

Is this good looking software in tune or off key?

TuneUp Utilities

TuneUp's interface is one of the simplest in our group test, giving a complete overview of the status of your system, with a progress bar at the bottom to show you how far into the process of tuning up your PC you are.

Although working through each of the options takes a while, you never feel lost among the wealth of options and settings. One-Click Maintenance works through all the most basic tweaks automatically, cleaning and defragmenting the Registry, removing broken shortcuts and temporary files, and optimising start-up and shutdown. However, we saw slight increases in startup and shutdown times.

TuneUp was the only tool in our test that recommended turning off visual effects in Windows 7 to improve performance - something that didn't even occur to us. The result was that Windows 7's sleek aquatic default theme was replaced by Windows 2000-era greyness, but it did feel slightly more responsive. Users of low-power netbooks might find this handy, but the necessary controls are tucked away in Windows 7 anyway.

Statistically, TuneUp sat on the fence, providing no great leaps in performance and only a slight improvement over Windows 7's native settings. LibreOffice loaded quickly, as did Half-Life 2, but the results weren't astounding.

TuneUp corrected 149 Registry entries, but this failed to provide a real boost in performance. TuneUp's problem-finding is divisive. Some users will find it intrusive, but less experienced users might like to know about the issues it flags up.

One of the first things we do when we install Windows is turn off User Account Control - we don't need TuneUp to remind us of the fact. On the other hand, it did let us know that Windows Media Player was broadcasting our computer's ID, which is something paranoid media consumers might want to turn off.

Verdict: 3/5

2. Ashampoo WinOptimizer 9

Ashampoo promises to clean and condition

WinOptimizer

Memories of John Cleese slapping his Spanish waiter spring to mind when a piece of software asks whether you want to activate your internet connection 'Automatically' or 'Manuel'. It's one of a many mistranslations or misspellings in Ashampoo WinOptimizer 9, and it's pretty indicative of the design.

The software's cramped interface includes a handy summary of your system's hardware and settings, along with maintenance categories, plus CPU and RAM speedometers. Optional settings like Live-Tuner and Hibernation File can be switched on and off from here, but WinOptimizer offers no explanation as to what these toggles actually do.

Fire up the Tuning Assistant and you're presented with a bewildering number of questions, as if you're filling in a job application form. People who know their way around Windows will find this survey easy to answer, but novice users are likely to find questions like, 'Do you use the hibernation status of Windows?' and 'Is Windows installed on an SSD hard drive?' utterly confounding.

WinOptimizer applies fixes based on your answers, and it was here that we found the one of the program's saving graces: an option to adjust USB polling. Windows checks for new USB connections every millisecond, but this can be reduced to every five milliseconds to save power.

WinOptimizer 9 did make a difference to the way our system ran, though. It came third in terms of Windows boot times, and although Half-Life 2 didn't boot that quickly, LibreOffice's times were among the best.

It feels like a piece of software that will benefit office and internet users more than it will gamers, and a decent Peacekeeper score backs this up. It may look a bit Fawlty Towers, but it's quite handy once you get past its shabby exterior.

Verdict: 3/5

3. Fix-It Utilities 12

Hands-off repair with a muddled interface

FixIt Utilities

Fix-It Utilities certainly has the best looking initial interface of all the software in this test. Boot it up and you're presented with three battery-style columns representing the optimisation, security and maintenance status of your PC, with a simple 'Analyse now' button. The application then finds every problem and, with a single click, fixes them.

Unfortunately, scratching beneath Fix-It's glossy surface reveals that there's not a huge amount to it. It includes all the standard features like a Registry optimiser and a start-up program killer, but nothing more. It feels as if developer Avanquest has invested a lot of time and thought in the interface, but forgotten to include anything but the most rudimentary of optimisation settings.

To make matters worse, it all becomes hugely confusing and poorly laid out once you get into the options. 'Active programs' reveals 46 running services, like Windows NT Session Manager and DcomLaunch, but fails to indicate what these are, other than 'Necessary'. Novice PC users will probably be bewildered, and run the risk of stopping essential services.

Fix-It performed poorly across all our tests, too. Our Windows boot time was slowed by a minute over the best-performing piece of software, and it was the lowest scoring in our Half-Life 2 and LibreOffice timed tests. Every result showed a substantial decrease over Windows 7's native performance.

There is one small piece of wheat among the chaff in the form of a file shredder, which permanently deletes files to 'US Department of Defense Standards' - although even this functionality is available in free software like File Shredder.

Much like a kit car, Fix-it initially looks the business, but taking it for a test run reveals its numerous flaws.

Verdict: 2/5

4. Iolo System Mechanic 10.7

Can optimisation specialist Iolo still woo us?

System Mechanic

Established in 1998 with the grand vision of optimising every PC on the planet, Iolo is the granddaddy of system improvement software. It estimates that it sells 85 per cent of optimisation programs in the US, and it pretty much created the genre.

With facts like those, you'd hope System Mechanic would be good. We weren't disappointed. The tool delivered astounding results in almost all of our tests, with Half-Life 2 and LibreOffice opening snappily, a best-ever Peacekeeper browser benchmark and a low Windows shutdown time. Windows 7's start-up time increased slightly, but not markedly. It also detected a staggering 260 Registry problems in our system - almost four times as many as some of its competitors.

Iolo has clearly invested a lot of time and money in ensuring a fluid, aesthetically-pleasing experience from its software. Boot it up and a set of meters estimates your PC's current health, with a nice big 'Analyse now' button to begin the optimisation process. From here you're presented with a summary of issues on your PC, with the option to repair them one at a time or all at once.

It also provides a suite of tools for ongoing optimisation to ensure that future problems are nipped in the bud. Each automation, like start-up configuration and detection of low memory problems, can be toggled on and off, and clear descriptions mean new users won't feel out of their depth.

Further tools provide more tweaks, like acceleration and Registry revitalisation, and none of these feel tacked-on. System Mechanic is certainly the best all-in-one product in our test, and it spruced up our beleaguered operating system to levels far above its original installation. Our only complaint is the desktop widget that installed alongside System Mechanic, but fortunately this can be turned off quickly and easily.

Verdict: 4/5