computer turns off at random

I have a problem with my computer where it will shut off and then restart after being off for about 5 seconds. it does this about once a week. Could this be a bad power supply? could it be word that is doing this? it just restarted again (second time in about an hour). I know I was in word the last time it restarted, I don't remember if I was the first time. I know that I have been in it in the past when it restarted.

EDIT: I just ran a memory scan and found no errors. so rule that one out. bad motherboard?

anyone?

I would think the first instinct of a dodgy PSU would be correct .... Usually with memory problems you'd expect some kind of critical stop ...

Have you got a volometer to check it?

Also what psu are you using?

volometer?
the psu is a 500W turbolink. i failed to mention that the computer will freeze when i go to put it into standby. (the hard disk will power down, but all the lights and fans on the case remain on)
Anyone know of a good, free hardware test program?

Volotmeter is a handheld tester for electrical circuits ....

There isnt really a hardware test program. You can use a program like everest and view bios reported voltages but this still relies on software and can be wildly inaccurate ....

You could use a psu tester. Its a foolproof handheld device that you hook the psu directly to. It reports exact voltages without the possibility of any errors from software ... I have one and its saved me alot of money and time ....

http://www.newegg.com/Product/Produc...k=psu%2btester





The standby problem could be related or it could be vista entering power save mode on certain devices and then not awaking properly ....