Computer reboots while gaming

[StAtIC_ak]

Hi guys i really need your help.
I dunno why and how my computer reboots without any error message while playing games. I thought it maybe my PSU prob and i bought a new 500W PSU but still got the same problem. Maybe a corrupt OS (windows 7- ultimate 64bit) and yeah my Gpu goes 94 degree+ and has gone over 104 while gaming but when i start my pc its temp is aroung 64*C which again i guess isn't normal.
Amd Fx-8350 processor
Nvidia Geforce210
HyperX 8gb ram
windows 7 -ultimate 64bit

[Calum]

Your GPU temperature definitely isn't normal for that card, does it have a fan and if so is it working?
I suspect it's either badly clogged with dust or that the heatsink isn't attached properly, those temperatures could certainly be causing this issue.

That aside, what make and model of PSU did you buy?  Bad PSUs are also a common cause of random reboots.

[patio]

Nice choice on the italics...