Lately I am having this really annoying issue with my PC where just out of nowhere, randomly shuts off without any errors or any signs that its going to shut off. This only happens when I play Black Ops 2 and sometimes, (very rarely) while playing Minecraft. If I am not playing any games its all good. It also shuts off faster if I play Black Ops 2 and record. It usually turns off after about 30 minutes of gameplay. While recording after about 10 minutes. It only happened once while I was recording Minecraft Hunger Games.

So my specs are as follows:

CPU: AMD Athlon II X4 645 3.1 GHz
GPU: Radeon HD 7750 1GB
Motherboard: ASUSTeK M4A78LT-M
RAM: 4GB DDR3 10600
Power Supply: WIN POWER ATX - 450W

Any way of fixing it? I read that it might be because of the power supply, that its not enough but my friend that plays Black Ops 2 with me all the time never had that problem and he has 250W or something like that. I'm thinking that my RAM is getting screwed up but I'm no expert so thats why I am asking you guys. Thanks in advance