I have a box with a Tyan motherboard that is driving me nuts. Trying to install Ubuntu from external USB CDRom. Can't even get to BIOS with a SATA HD in the box. Says "entering setup" but then displays name of HD and hangs. Remove HD, I can get into BIOS, where I disable all boot devices BUT CD. With no HD, I can boot from CD fine.
Reattach HD, power up, same problem... sees HD, stalls, won't go past displaying the name of the HD (whether or not I hit Del to access BIOS) despite the fact that HD is supposed to be disabled.
Probably the hard drive is bad, but have you tried waiting a long time for the computer to respond say 15 minutes or more, or you could try fitting the hard drive to another computer and reparation and reformat it.