PC freezes when running some games

[james12389]

This is a recent problem, but when running some games my computer crashes for no apparent reason. The problem also varies from game to game - running portal 2 on low settings causes the computer to freeze within a few minutes. However playing company of heroes on maximum settings has yet to cause any such problem. It hasn't happened when doing anything other than games but has crashed so far running Portal 2, Starcraft 2, EVE online and Battlefield: Bad Company 2 - though I've never had a crash on bad company prior to this week.
I'm currently running an Nvidia 8800GT.
Checking error logs for the crash gives a crash error with a powerbuttontimestamp value of 0.
I've checked the memory which found no errors and nothing on the computer is being overclocked. Microsoft suggest it could be a lack of power so this could be plausible - though I have a 450W p.s.u and the fact it's only recently occurring on battlefield makes me think this isn't the case.
Also when it freezes even caps lock doesn't cause the keyboard to light up so the system is completely unresponsive.
Any help or advice is much appreciated!

[CAT-THE-FIFTH]

What is model number of your PSU BTW??

[james12389]

It is apparently a HEC-450VP-2RE according to the side.
Can't run half-life 2 either now

[CAT-THE-FIFTH]

It could be your PSU or graphics card going kaput?? I assume when you are not playing game your system is fine??

Have you upgraded the graphics drivers recently??

HEC is not the worst PSU brand although some of their ranges are meant to be not that great IIRC.

I would make sure that you give your system a good clean out to remove any dust and also make sure that the PSU and graphics card fans are working.

[Zak33]

sounds to me like a heatsink needing frsh thermal paste

[james12389]

It could be a heating problem but according to the Nvidia monitor, the CPU is at a comfortable 26-28 degrees most of the time and playing games the graphics card keeps to about 77 degrees, which I've been told is fine for an Nvidia card.
I have the most recent graphics drivers so I don't think it's that, I'll give the computer a good clean out tomorrow to see if any crap is causing a problem and I'll see if I can get any thermal paste to put on whilst I'm at it :].
I've yet to have a crash doing anything other than gaming.

[CAT-THE-FIFTH]

Have you recently upgraded the drivers though?? Try some older graphics card drivers.

Remember when gaming your system is under a heavy load so this is why the PSU can be the source of problems. However,unless you have a decent PSU to test or a multimeter it is hard to say.

[james12389]

I'll roll back the drivers to some older ones now and if that doesnt work I'll look at a new PSU soon :] thanks

[Joeroe_92]

try turning down the maximum cpu output percentage on windows power settings to 80 percent and running it then