My computer randomly switches off, no BSOD.

Bobby,
I see what the confusion is.

copy following using Crl+C.

Code:

wmic computersystem get /all /format:list > %userprofile%\desktop\computersystemall.txt

run cmd.exe
Paste using RIGHT-CLICK (ctrl+v will not work)
that will put a file on your desktop called computersystemall.txt


In there you will see mfg, model, etc.

bobbyblue said:

Now it just reboots

Elucidate.

you can:
1.test your memory with Memtest86+
2.test your hard disk with SeaGate Tools for DOS
3.replace the power supply
4.replace the mobo
5.clean install Win 7.

Just work your way down the list until the system works.