3. JV16 PowerTools - £19

JV16 Powertools has quite possibly the most aggressive sales website we've ever seen: "You must act now and make a copy of JV16 PowerTools your own. There is no other sensible choice.' It's the only way to be sure.

It is one of the better optimisers, though, and its beauty lies in its incredible depth: it allows you to tweak your Registry to your liking, and tells you what each entry is responsible for.

JV16 powertools

It also includes a Registry compactor, which attempts to reduce the loading time of the registry by compressing it to a size that's manageable by your computer and runs in the background to keep things ticking over.

But being in-depth is a double-edged sword, and it's not the easiest software in the world to get your head around, and it doesn't have a one (or two)-click optimisation system. It also didn't make a huge difference to our boot times.

We'd recommend this for people who like to get their hands dirty with their PCs, but it's not for grandads or simple people.

4. Iolo System Mechanic 9 - £25

We've looked at System Mechanic before, and we were rather impressed with the sheer amount of stuff it packs in its slender box. Not only does it clean up your Registry, it will also remove Startup programs, speed up your internet and defrag your hard drive and memory. Too good to be true?

Possibly. In spite of Iolo's claims that it can make Windows up to eight times faster, it actually increased our start up time, and the difference in Mass Effect 2's bootup speed was negligible.

System mechanic

It also proved problematic when we tried to do a system restore: for some reason it had removed our backup, which is massively intrusive and actually quite dangerous. We dread to think what else System Mechanic 9 did inside our machine. It probably emailed our personal details to the KGB or something.

You're far better off investing in a dedicated registry editor – like JV16 PowerTools – than this jack of all trades.

5. PC Tune-Up 2.0 - £25

PC Tune-Up is undoubtedly the most polished piece of software in our test, and it's easy to use. What's more it sports a lovely interface so you can see exactly what's going on thanks to the giant icons.

It went through all the bits of the PC, making tweaks and adjustments and then… it just stopped. The PC completely crashed, and we were forced to reboot.

PC tuneup

PC Tune-Up had obviously done something right, though: it was the fastest boot time of all the products we looked at, and it didn't bombard us with information and pop-ups upon booting.

It's nice and simple, and definitely does the job, but we can't comfortably recommend a program that mysteriously crashes whenever you use it. It does seem to be the best of a bad bunch though, for those that don't mind paying.

6. Free Registry Cleaner - Free

The other Free Registry Cleaner in our roundup is by far the simplest – offering little more than a Registry tidy up – but it is rather brilliant for exactly that reason, and it's completely free.

It's not quite as polished as other efforts, but what do you expect from something you don't have to pay for? It even packs in a couple of nice features, such as being able to see which programs fire up when you boot your PC, with the ability to turn them on and off.

Eusing

We were stunned by its performance, too: it outranked all but one of the paid-for softwares. It's a little low on other features, such as deleting files, but we reckon if you use it in conjunction with the similarly free Ccleaner you'll have a completely optimised PC.

Best of all, it's a nice small package and it doesn't wreck your computer, crash or load up lots of annoying extras on start-up. It's ironic that the only pieces of software in this test we want to pay for are free.

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First published in PCFormat Issue 237

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