Entire system lagging sporadically while playing left 4 dead

[BlackScarlet]

Exactly that. I've never had a problem playing l4d before, and now, i cant play for twenty minutes without my entire system lagging down to at least 1 frame every two seconds. like for example, i type seventy words a minute and its just filling in 'twenty minutes', thats how far behind my type it is. it lasts about fifteen minutes before i can go and play my game again aor watch a movie or even move my mouse and see where it sgoing. i have onno i dea if there are typing mistakes in this post because it's not even a firfth of the way displaying what ive typed. my system has downs sydrome. why??!?!?

I don't know wahat the problem would be , considering ive never had a problem with this game before, and its not even consistent. its like every twenty minutes or so my video card memory decideses to go and get a coffee alongside my ram.

I've got a nforce 8600 gt 2G ram, and intel dual core 2ghz on win xp.

 

[mailpup]

It might be overheating. Try removing the graphics card and removing all the dust that may have accumulated inside. Check the cpu heatsink for dust clogging as well.