During install the SCSI CDROM module gets loaded before the SCSI DISK module. This means that the CDROM gets /dev/sda and the disk from the PERC card gets /dev/sdb. On first boot they swap and Debian stops because it can't check /boot. This is an unfortunate circumstance for Debian, and the guys writing the installer should really change to using UUIDs, but that is another discussion.

When the system halts during boot, log in with the root password, and then edit /etc/fstab and change /dev/sdb to be /dev/sda, save the file, and reboot. If you are adventourous, you could set the UUID in /etc/fstab instead. I will that up to the reader as an exercise.