Computer keeps rebooting

[shibbii]

on one of my computers, whenever someone plays games on it.it reboots. i have no idea what the problem is.i thought it might have been ram so i upgraded that.it now has 768 and it still reboots.anyone able to help?

 

[Crysalis]

overheating? video card not able to handle it? SPECS!!! WE NEED SPECS

 

[Ste]

So your saying you had a stick of either 512 then added a stick of 256? Or a stick of 256 and added 512?

Try taking 1 Memory stick out.

I assumed this cause you said you upgraded and now have 768, what? I guessed memory cause 1 stick of 256 and 1 of 512 == 768.