Pc games suddenly stop working

Whenever I play any game on my computer about 30 min to a few hours into the game it will suddenly exit out and windows will say it stopped working. I used to have xp with 32 bit and it never happened, i switched to vista and it started, then i switch to windows 7 hoping to fix it but it still does it. Anyone know how i can fix it or whats wrong? Also when i switched to vista i started using 64x OS and added some ram.
My specs:
Win 7 ult. 64x
q9300
6gb ram
Asus p5q se2 mobo ( i think)
9800 gt
600w PS

and some of the games i've been playing that it happened in are HL2:dm and fallout 3.

update gpu drivers?

Graphic card. overheating.

Yep.

i have the newest drivers but i guess i'll dl precision and turn fan on high, thanks.

Had the same problem, me graphics card was overheating. Logan the wise one told me to clean up my computer, and make sure the fans weren't hitting anything. Also to make sure the PC was in a well ventilated area. :3

Just monitor your temps and if they are too high turn the fan speed higher.

it probably didn't help but i broke my 230mm fan last week.

PC ain't got gayumz.

The main thing is that your rear fam(s) work and exhaust warm air outside.

try looking in the case and looking at your GPU fan or CPU fan but the probllem IMO is GPU fan being clogged with dust!

Seriously rice? FUCK OFF with your stupid shit.

... Dont feed the troll

what brand psu you have. if its generic it can get tired after sometime. look at your psu and find how many amps it has

Yea it could be GPU drivers, maybe the graphics card is overheating though. Im not sure.
If its not those two its most likely the
GIANT ENEMY CRABS, and i suggest you hit its weak point for massive damage

+1

and the added bonus of $599 USD

RIDGE RACERRRRRRRR

i used to have the issue, it ended up being a non responsive gpu driver called nvlddmkm.sys
if that is the problem i have a fix for it.

http://www.ocforums.com/showthread.php?t=518749Â

worked for me on vista. havent had the issue on windows 7 yet but i guess its just a matter of time.

alright. first of all I dont have that error in half life 2. the only game i get it in is Fallout 3 which you listed. I was reading on forums and many people are having an issue with running fall out 3 on 64 bit vista . are those the only two games this is happening to you in?