I disconnected all drives except the CD/DVD and one HDD. The HDD is on SATA3_0, the first Intel port, and the CD/DVD is on SATA3_1. With the boot order at CDROM, then HDD, and a Linux install CD in the drive, it boots immediately and I was able to install the OS, and boot from it, on the HDD.
However, when I disconnect that HDD and put the SSD -- the previous boot drive -- on SATA3_0, the machine will not boot off the CD, either via boot order or F12.
It does boot off a CD with all other drives disconnected.