Why would my system reboot by itself?

[snidy1]

I know it's not a virus or spyware because I just reformated. It only does it every couple days. It's not a heat issue because it happens while idle sometimes. The only thing I can think of is maybe the power outlet. What do you guys think?

 

[ShawnD1]

When my system did that, it was because of a leaky capacitors on my motherboard. It can also be caused by a crappy PSU.

 

[bob4432]

2nd the power thought

 

[littlebitstrouds]

What is the power unit are you usin? most times a restarting computer is due to a rail that drops

 

[ISAslot]

Are you running XP?

Do you have reboot on error still checked?

Any errors in your system log?

 

[ponyo]

Check memory or PSU. Run memtest to check the memory.

 

[snidy1]

I'm using an Antec true power 500W so I don't think it's the PS. I'll try memtest.

 

[snidy1]

Do you have reboot on error still checked?

How do I check this?

 

[Tostada]

Like ShawnD1 was saying, when your computer starts rebooting, if you haven't changed any hardware recently, the first thing you need to look at is the capacitors on the board. Any capacitors that aren't perfectly flat on top need replaced. This is a very common problem with motherboards made in 1999-2002 because there were a lot of faulty capacitors used on motherboards from several vendors then, but it can be a problem on any board.

I have a Shuttle SV-24 (their first generation SFF machine) that I was about to throw away, but after a quick soldering job it works fine.

 

[snidy1]

It's only a year old, but I'll check the capacitors anyway.