Something is horribly wrong.

I ran memtest86+: it finished with no errors.

I also removed the Video card (and ran directly from the on-board video).

Blasted it very good with air and cleaned everything out (wasn't too dusty (I was surprised).

Rebooted a couple times and it froze doing various things. (I was trying to backup all of my data to another drive and it froze at various points, no consistancy, also when I ctrl-prntscrn'd the HWMonitor results. Locked up good. I couldn't shut it off holding in the power button. had to unplug it! ).

I also upgraded the BIOS to the latest version and installed a brand new battery.

Still froze.

A couple times it crashed on the reboot and gave me a message:
"Overclocking failed! Please enter Setup to reconfigure your system.
Press F1 to Run Setup
Press F2 to load default values and continue."

believe me, it is NOT overclocked. I loaded the defaluts and only changed the boot sequence to boot from a CD. I received this message before and after the bios upgrade.

I also tried to re-install XP, from a Slipstream version I've run several times before flawlessly. Both times, it crapped out during the first couple minutes, informing me that a file was corrupt. (I seriously doubt it and even burned a new ISO and tried it just to make sure.)

I tried to run Real Temp, but it said the "Processor was not supported".
I checked the components by hand and nothing felt hot, just warm.

I did run HWMonitor.

nothing looked unreasonable.

Any suggestions? I'm stumped. I've been at this all day and I'm ready to throw it out the window!

suggestions? please!
I really need help