O.K. When I boot up, I get the following message: "cpu is unworkable or has been changed" followed by "hit f1 to continue or del to enter setup". The computer will not boot into windows unless I hit f1.

Also, sometimes after shutting the computer down and then trying to restart it, it won't turn on. It starts to come on, the fans start, then after just a few seconds, it shuts down again, the green power light staying on. And here's a strange thing. I opened the computer up and noticed that when this happens--after it had failed to boot and the power light is still on--one of the case fans and the cpu fan are turning, but at a very slow speed. These fans stop if I unplug the power cord.

So, what do you think? I'm leaning toward this being a power supply issue? Second thought is that I might need to replace the motherboard. Any thoughts or comments would be greatly appreciated.

Motherboard= Abit NF7-S
Processor=AMD Athlon XP 2.8 G

The answer to question 1 is that you need to go into the bios,set the options then save and reboot.
If you get the same message upon reboot then your mobo battery is likely to be dead.

Tt Lanfire
MSI K8N Diamond
AMD64 3000+'Venice'
1gb pc4400
OCZ Powerstream 520w
6600GT
WDCaviar 160gb sata x2

;~}

The fans running slow make me think you should also try swapping the power supply.