Sounds like your HDD is bad. Uhh lets see here...
-rumages around in the papers under his desk-
Here it is:
Ahem, There are two options you can choose in such a situation one of with requres renstalling your OS the latter of wich requires a hammer. Myself prefers the latter. Anywho, Pull all of the plugs out of your drives check for bent pins check for bad temination check for bad cables then put it all back together, reset your BIOS settings and redetect your drives. Then try booting. Rememberr this termination: HDD with your OS is the PriMaster the second HDD is the PriMaster. Your CD/DVD rom drive is the SecMaster and your CD/DVD-RW drive is the SecSlave. If you dont have a second HDD or a second CD then just exlude them from the list. I have had very bad expirence with placeing a CD and a HDD on the same chain. But should you need three HDDs or three CDs then I guess you can. If your computer still does not boot up then place the OS CD in your SecMaster drive and set your computer to boot from the CD. If your computer does not support this, you have a reall sad computer. In witch case set your computer to boot from the floopy drive and insert your EBD.(Emergency boot disk) If this solution fails to solve your problem please contact customer support.
This is writen on a tettered pice of paper under my desk.(Except for the "then you have a really sad computer" part)