I have had this exact problem!  In my case, it was the IDE zip drive that 
was causing the problem.  You need to change the BIOS to "none" instead of 
"autodetect".  I would agree with the other respondents as well, be sure 
your jumpers are set right (esp. that you have master or single set 
correctly.).  If you have any removable media on your IDE channels such as 
the already mentioned zip drive, change the BIOS settings.  Let us know how 
it goes!