Had a weird problem trying to install OpenBSD 3.5 on an older system I had. The BIOS could boot from the CD I had made but the system would get to the boot screen prompt and would just sit there doing nothing. After screwing around with it for a while I finally figured it out. The CD Rom drive that I was using was trying to boot as the primary on the second IDE channel. Well this Intel mobo must not have liked this and would only boot if it was the master on the primary IDE channel.