Probably it's not going to work out.
A DAC960 won't work with RH9 at all unless it has a v3.5 or newer BIOS rom. Trying repeatedly doesn't always yield similar results...but it never works. Older versions of the board have no flash capability, and therefore you're sunk AFAIK. (At least for RH9)
As for why it's not finding the 2940, and the CD attached to it, that's an interesting question.
Troubleshooting, troubleshooting. Remove some variables.
Take the 960 card out temporarily, and connect any old drive to the 2940 along with the CD ROM. See if it finds it then. If not:
Take any old IDE controller - Promise, or one of those CompUSA ATA controllers (presuming you have ANY PCI slots) old ISA creative labs one (if not) and connect an IDE CD-ROM, with the HD still connected to the 2940, but no CD rom.
You could have bad hardware, incompatible hardware, or hardware that won't work in the same box. You don't say whether this stuff has worked under some other OS in the same configuration (meaning the hardware doesn't have other conflicts we are unaware of if it has)
Good luck. Let me know how you make out...and if you want some 960 PCI cards cheap.
B