PC Restarts mid-game randomly

[sniper360]

My system is listed below. I play H&G often and randomly the PC will shutdown and restart on it's own. I figured it was time for a new CPU cooler, so I mounted the EVE 212 I have and it still happens. During the game I generally get 100-200 FPS even at stock speeds. The temp ranges between 40-50 solid (that I can see).
This only happens with H&G. I have tried the following:
Replaced CPU Cooler; Reseated all components; Underclocked it; Ran all fans at 100%.

 

[Snipergod87]

Are your specs the ones in your sig?

 

[officalsyco05277]

Is it cracked version?

 

[sniper360]

All the components listed is the surrent rig with the exception of the PC cooler which I swapped out and got the same results.

 

[sniper360]

H&G on STEAM...

 

[sniper360]

Iv'e never had a problem in the past...just plain weird.

 

[sniper360]

H&G both on STEAM and through Chrome. I fixed the problem by adjusting RIVA Tuner to hold at 55 FPS. Hasn't crashed since.