General Bios question

[Dando52]

Specifically this concerns an HP 8280 w/333mhz intel processor 128mb pc133 ram with dvd/hp model 9300series burner/maxtor 40gb hdd/fdd/integrated 3d rage pro agp 2x video/sound blaster audio card.

the Bios keeps independently changing its settings. Have checked voltage on cmos battery which shows 3volts +. Have double checked master/slave settings on hdd and cd rom drives. Have replaced ide cables.

The problem is that sometimes it reports the presence of dvd and or burner and sometimes it does not. Of course windows mirrors the problem.

Any suggestions?
also, if the dvd or burner has gone bad can anyone explain why the bios can't see them?
Thanks for your help whoever you are!

[ski]

It's very unlikely that both the DVD-ROM and CD-RW drives have simultaneously gone bad. It's more likely to be a bad cable or IDE 2 controller.
Make sure the new IDE cable is securely inserted at all connections, and the red stripe on the side of the cable is next to pin 1 on the MB and is facing the power cable on the back of the drives. If that's ok, then it may be a bad controller.
Does Device Manager show any problemw with the controller?