UPDATE:

took it to the computer store here and they tested the PSU, they said it was working after running a test.
Anyway I handed it in so they could find out what was the problem and after a week they called me and said they put a new (much louder PSU) inside and the computer was working again.

The ram is fine, so is the CPU. I am convinced the mobo is fucked.
I might need a new computer.

Thing is, it restarts every now and then, like it would if it overheated but it isn't actually overheating. Something is wrong with it and im stumped.

Symptoms.

*Freezes under average usage
*restarts when im watching a vid, using iTunes and have firefox open.
*heaps of other shit like when I start the machine an error message comes up before the XP user login window with usually has gibberish symbols (squares mostly).

I thought I might have a graphics card problem. guy at the store said he found loose screws in it. lol.

But seriously gettin irritated by the suddenly sick computer.

Might try installing XP again or go to win7 64bit and buy more ram. I know my mobo can support it.
Ill try xp first, if it doesn't fix it then....
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