System shuts down

[crphillips]

Please can anyone help....built a cheap system for a friend out of some oldish second hand bits.....basically i don't know what half of the bits are.

The processor is a 1Ghz AMD with 256mb memory and all the usual stuff plugged into it.

The computer boots up fine and works great but every now and then it turns itself off and will not turn back on with the power button on the front of the computer. It will only reboot if you turn the mains off and back on again. My uncles computer used to do the same and i am using the motherboard, graphics card, USB/Firewire card, Memory and Processor from that system.

I don't know whether it is me or not but its seems to do it most when you try and do two things at once......for example....writing a document in word and burning a CD.....

My first diagnosis would be a faulty motherboard? does eveyone else agree?

Your help would be much appreciated

Cheers

Chris

 

[Yeti]

My first guess would be the power supply. Try watching the voltage rails.

 

[crphillips]

power supply

I thought about it being the power supply but it did it in my uncles computer too which is a different power supply.....

Cheers

 

[Bigshow1030]

temp

automatic temp shutdown of some sort?

 

[crphillips]

that is possible

that could be possible......i haven't set an automatic temp shutdown but i suppose it is possible that it could have a default shutdown temp. will check that out....cheers