Computer not recognizing CD Rom

I have a DeLL Demension 8100 that I purchased back in 2001. I upgraded it from windows ME to XP Home. I also installed a Phillips CDR-RW a few years back as well.
The problem is that my computer just stopped recognizing the cd rom drives about a month ago. When I start up the computer, I get a message that says:
Diskette Drive 1 failure
Secondary drive 0 seek failure
Secondary drive 1 seek failure

I have gone to the system BIOS and it says the device on these two drives are unknown. I have no idea how these two are supposed to be set up?
Next, I exit out and skip system bios and start windows back up and everything comes up fine. The problem is that I cannot access the cd rom drives. There is nothing even suggesting I have a cd rom in the device manager or my computer. When the computer starts up, the lights come both cd rom drives. I have opened up the case and there are no loose wires. Last month I was so frustrated that I but in xp boot disks into the a: drive and reformatted the computer. By doing this, I lost all my data, but the drives came back. Now I am back to square one!

I have heard that using a USB memory device can cause conflict, but that is all I know about that subject.

Would appreciate any help.

If the BIOS can't find it then Windows won't either.

Check the CDROM drive cable, unplug and replug all the connectors. Swap the cables with the hard drive.

I have tried all that before with no luck. The only thing that corrected it was when I put in the xp boot disks in and reformated the hard drive. I don't understand why this happened again.

You may have a failing IDE controller on your motherboard. Or maybe one of the CDROM drives are going bad.

Try the CDROM drives one at a time. Put the HD on the controller your CDROMs are on and the CDROMs on the primary controller.