Computer restarts while gaming max payne 3


Jul 26, 2012
hi guys, i recently upgraded my computer to 8gb of ram, and have just installed a gtx 580 which works fine, or so i believe.
the problem is when playing games such as maxpayne 3 and arma 2, and occasionally world in conflict, my computer restarts itsself with no error messages, and no evidence that anything is wrong. i do not overclock, and my system is squeaky clean from dust. the temperature under load is around 50 - 75 depending on how loud i can be arsed to have the fan on.

the weird thing is i can make it happen. f.e anyone familiar with maxpayne 3 will know about the final killcams. if i do any of these using a shotgun, blam insta restart every time. the same thing when i pull one off from extreme range with any weapon. i have good fps, and low temp , so im not sure what to think, ive read it may be a power issue ? is this true? and if so why does it happen so predictabily, my powersupply is very basic, off the top of my head it just meets the gtx 580 requirements, and is of less than awesome quality.... please let me know any thoughts or fixes, thanks.