PC reboot with BSOD while Farcry2..

Okay here is my problem i am having this sudden blue screen and reboot problem while playing this game...its not the common sound card problem with far cry 2 like others did..i have this problem after playing a decent amount of tym..sound driver causes bsod just after the load..thats not my case.plus i am running a buil in sound card..
it hasnt rebooted in other games yet..

i myself think it can be caused by two things..
1. In the eventvrwr it show ERROR- nv event- 14 which an nvidia error..i have the gpu of this brand..(nothing else)..maybe not enough power supply.. this is how my eventvwr looked lyk-

http://img20.imageshack.us/img20/1185/30052007013.jpg

2. one of my rams are non branded chinese ram..its not detected by the mobo when its fully inserted in the slot..it only works when its loosely fitted.(i know its weird) ..

but if it was the ram problem it wouldnt show nv error on eventvwr wud it?please help.

my specs are-
gigabyte g31 mobo
xfx nvidia 9600gso ddr3
2gb ram
cpu-e2160
160 gb HD
420w thermaltake 12v. psu.

(sorry bout my english)

In this case, you maybe need to update your drivers from NVIDIA. This seems like a software issue. In the worse case, you may need to re-install Far Cry 2. If everything is OK before running the game, try updating your drivers first.

iam so f****** confused!! becuz there might be so many things-

1. if i remove the chinese rams..sometimes the pc wont start..(may be both of them are gone!!)if u are thinking my mobo is gone...i have just got a brand new mobo changed of warranty (the old one had somewhat the same problems..never showed blue screen though..but it restarted even on desktop sometimes)

2. The farcry 2 i was using was not even installed in my pc.(it was before,but i had to re installed my XP so..the registry was gone..but it was still working..so didnt reinstall it..now i ll give it a try)

3.i don think its a farcry problem...i read it somewhere a software can never give u blue screen..only hardware can..

4.my hdd is old but it has no bad sectors i have checked with disk doctor..


.............its f***ed up...ohh.. this is f***ed up..