Stuttering in games (crysis, cod4)

Spunge

Earlier in the week i was getting artifacts and crashing in my games like stalker and crysis, it turned out my gpu fan was clogged with dust, so i removed the dust and the problems stopped and my fps in crysis went up a few frames.

It was working fine for a day or so but then, yesterday, while playing crysis (low @ 1280*768) online the game seemed real chuggy, i thought ok, i put on fraps but my fps wasnt low at all it was 30-100 depending on where i was. Its like a stuttery feel when im turning around and it gets somewhat worse during the match.
It was happening in call of duty 4 also, but not as bad, but still annoying as the game usually runs perfect.

Just wondering if anyone can shed some light on the cause.

I tried re-installing gfx drivers and mobo drivers but seems the same.
Last resort would be re-install windows but i got so many games and stuff to back up (i know ill forget something) that id rather not do it. I de-fragged the HD a week or 2 ago, also.

Here's the rig:
e4400 C2D
x1950 pro 512MB
2GB 667
Fortron 400W
250GB 7200RPM

rrpc

Stuttery performance is either the gpu being overworked or could also be RAM not being sufficient and Windows is using the hard drive for extra memory.

There's also a possibility that your bandwidth dropped online, but it would have to drop significantly.

Try playing offline to eliminate that as a possible cause.

Anti

could also be something running in the background like a AV or spyware. im not sure if the 1950pro is well enough to handle thouse games properly, but it should be fine.