First remove the pins from all your IDE devices and see if the problem is resolved. If that doesn't work pin them all as "CS", and if that doesn't work pin the CD/DVD as master and the primary HD as slave then try and boot to a CD/DVD. Monitor the post on boot to see what configures and what doesn't.
If nothing works - unhook all the drives and the power leads to those drives and see if then you can get back into the BIOS.
Answers & Comments
Pull the battery off the mother board for a couple days to reset the bios
First remove the pins from all your IDE devices and see if the problem is resolved. If that doesn't work pin them all as "CS", and if that doesn't work pin the CD/DVD as master and the primary HD as slave then try and boot to a CD/DVD. Monitor the post on boot to see what configures and what doesn't.
If nothing works - unhook all the drives and the power leads to those drives and see if then you can get back into the BIOS.