Cpu works at 100%

[SlimDeath]

You may have dust inside your computer,so check it first.. (happened to me many times).
Notify us if it's ok now.

[knev]

if your application is using the extensive CPU, then could be problem in the application design. May be the application not suitable for certain hardware design

[Preeminent]

Close other programs and stuff while playing.
Keep your computer in a ventilated place.

[Ristov]

Your problem is the overheating. Well that's what I think it is.
Open up your tower, get something what Omniscient posted, if you are unable to get that then please get an air processor and clean it. DON'T DO IT WITH A HAIRDRYER OR A VACUUM CLEANER, or it will probably get damaged it if you do so.
If that doesn't work, then just try to change your OS or something.
My laptop's CPU temperature is 85 Celsius all the time.

[versx]

Do what Omni said, if that doesn't work then if you can, go buy some thermal compound for your CPU and reapply it. The stuff that's already on it could possibly be all dried up.

[Figaro]

Yeah, I would recommend placing some more fans in your computer. I am sure that this will help keep your system cool.

[Thoth]

My laptop does that, it's because it's a piece of crap imho.

[Figaro]

My laptop does that, it's because it's a piece of crap imho.

Yeah, I had a laptop that used to do this. But then I got a better one, no problems since then.

[haphazard]

install linux....
Daul boot and watch the memory performance

[Jet]

If you made the computer, try adding more or better fans or upgrading your RAM. If it's store bought, just contact your computer's manufacturer, they will be glad to replace it.