I have a Compaq Presario that constantly reboots itself. It just abruptly cuts off and starts again as if I had pulled the plug, plugged it back in, and pushed the power button.

I recently installed a new hard drive, DVD drive and added a stick of RAM. I assume this is what is causing the problem.

Compaq Presario:

AMD Sempron 3200
Windows XP Home - Service Pack 2

Reboots when?

When booting? Does it ever boot? Does it always reboot the same?

A new slave drive? Or did you reinstall XP?

Does the RAM match the existing RAM exactly?

The system will boot normally into Windows. I have not noticed any pattern i.e. open programs, time after reboot, memory usage...

I installed the new HDD as a slave.

Systems Properties reports RAM 960MB. I installed a 1G stick.

What is the exact Presario model?

So now you have only the new stick of RAM?

Are you sure the RAM is compatible?

Is the Graphics onboard?

If you remove the new hardware is the problem resolved?

Did you load SP3 or do you have Automatic Updates turned on?