Will not go past post sometimes

[Hollis]

Hello,
I have a Dell 2400 that sometimes will not go past POST. It appears to finish POST, but when this happens, I cannot get into safe mode or setup. I just get a blinking curser. This happen after trying to load an audio driver (the wrong one) and I got the blue screen of death. I have run every diagnostic program I can find and have found nothing wrong. I cannot get it to fail now, but have taken it back to friends home and it would not load windows. Maybe it will be fine this next trip. Any thoughts?
Thanks

 

[mister g]

There should be pins sticking up on a CMOS panel on the motherboard, got any free jumpers to attach to the reset pin? Otherwise remove the cell battery on the mobo and wait ten seconds to replace it.