What to do? Bring it to a repair shop. This sounds like some hardware error. I think a new motherboard might do the trick, but it might be it's something smaller.
Hope this helps.
PC with XP Home won't boot and won't boot to CD (won't recognize CD drive). Cant get to desktop, Windows, etc
i've replaced the CMOS battery; reset all (F1) "start up" settings back to, boot order - floppy, CD, HDD, Network. Tried to do System Restore (F10). I've tried to boot to System Restore disk, but unsuccessful since the unit won't boot to the CD ROM. I've even tried a wipe disk to start from scratch.
Hmm, what to do?