P6831FX Hardware Malfunction?

Hello, fellow FX owners and others...
I recently bought a P6831FX and I have done a clean install (after using gateway program thing to back up everything on DVD+R disk). And because I didn't like all the pop-up stuff that asks me to allow things to run, I turned that off. I also turned off back-up thing from the control panel. But the problem I have is that my computer randomly crashes. It crashed when it went to sleep mode and I turned it back on, it crashed when I close the lid and open and turn it on, and it just randomly crashed once. When I restart the computer, everything works. I can use internet, like how I'm using it right now, however, at the bottom right corner, the wireless thing has red "x" on it and when I put my mouse pointer over it, it says "Connection Status: unknown" "Server execution failed" Also, the sound doesn't work. The speaker thing at the bottom right shows that it works fine, and when I go to device manager, it says its fine. I tried re-installing the drivers for both the wireless and the sound, but they aren't fixed. After I did a clean install twice now, because samething happened before. After the formatting, it works fine, until it crashes again and the same stuff all over again. Does anyone know what is wrong with it and if I should send this thing in for a new one? Sorry for the long writing and thank you for taking your time to read this.

Edit:
By the way, my computer never crashed when I ran Call of Duty 4 with maxed out settings and I never over-clocked or anything. It seems to crash only when idle. Also, it doesn't crash everytime it went to sleep and stuff, it only crashed sometimes. I'm formatting my computer one more time tonight, so if anyone know solution, please give, but if you think its a computer problem, tell me if i should send it back for a new one.