>>Can you give a bit more detail on the cards in use? If they are ISA, the probability is you're in a good deal of trouble on interrupts, since ISA doesn't share IRQs.
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>Uh-oh :( I think you've cleared things up. The original SCSI is an ISA for an add-on internal CD. That means there isn't any way I can resolve this with both devices present? The two devices are the CD & that (new HP 6250C) scanner I was posting about a while ago...
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>The two cards are Adaptec ISA and a new Advansys PCI...

You can hang up to 7 devices on a single card. What Adaptec card, and what Advansys cards are you using? Neither of the devices is going to overburden even a 5MB/sec channel.

If the Adaptec card is working now, and there's an external SCSI connector on it, I'm sure that you'll have less trouble adding the necessary driver for the scanner to work in conjunction with the Adaptec than trying to get both cards in. Or if the Advansys has both internal and external connectors, and has ASPI support, I'd probably choose that, being a PCI card; SCSI CD-ROMs are supported generically though the ASPI driver, and if the card came with the HP scanner, there's no question of having support for the scanner.

Or pick up an Adaptec 29xx or the equivalent and scrap both cards - you could probably get away with the 2920, since neither device is bootable.