Narrowed drive problem down, kinda... can someone help?

[Superman]

I have two DVD rom drives installed in my pc. I set both jumpers to "CS." It seems that both are fully functional, so I don't think the problem is in the hardware.

The roms intermittently stop working. Like now, for example, they won't detect the disks that are in the drives. Earlier today, though, they were. Anyone know why a DVD Rom drive would sometimes work, but fail at others? The cables are plugged in. I suspect the problem lies in software, but not sure what I can do here?

Does anyone have any ideas?

[Starglider]

I suspect the problem lies in software, but not sure what I can do here?

PATA cables can be quite unreliable. The connectors can get dusty, and the connection between the conductors and the pins can degrade. If the electrical properties degrade without actually failing you get intermittent crashes. I'd suggest blowing out all the connectors and trying a different cable, if you have one.

Does this setup work when only one of the drives is plugged in (either of them)?

[Superman]

I have just one plugged in now, and it seems to be doing the same thing. I'll play around with it some more, but so far no change.

Thanks for helping.

[Netko]

Replace the PATA cable - even if it turns out it wasn't the problem you're only out of 3-5$. Especially do this if on inspection the cable is twisted or looks worn - PATA cables can relatively easily go bad.

Also consider doing a manual master/slave select (from your opening post I'm thinking you know how to do it, but if not its easy - just put the jumpers into the configuration for slave on one and master on the other - preferably master for a writer - there should be diagrams printed on the drive showing the correct jumper settings). While CS is nice, I've tended to find it less then reliable (then again, it not working is usually accompanied by one or both devices not showing up anywhere).

[Starglider]

Frankly it seems unlikely that it's a software problem if both drives are having the same problem, unless there's some kind of problem with the drivers for the motherboard that is screwing up the whole PATA controller. I've never encountered this though; the PATA interface itself is generally pretty foolproof, at the OS level.

Have you checked that a) these drives and b) that cable work in another computer? Otherwise I'd go with Netko's suggestion, replace the cable (and manually setting master/slave can't hurt). If that doesn't fix it and the drives work on in other computers, I'd suspect the PATA interface hardware on your motherboard.