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I have an Adaptec AHA-2940UW SCSI hostadapter to which I connected a single Atlas 10K III drive (and nothing more).

When my computer powers up it shows POST and then the option ROM from the Adaptec HostAdapter. Here I can see the Atlas drive listed many times (i.e. with ID0, ID1, ... ID5, ID7, ID8,...,ID15 [ID6 is the adapter itself])

Using the same HD on an Adaptec AHA-2940UB the disk only shows once

Since my OS hasn't been installed yet, I'm not sure if this is a problem (I would guess it is), and if so - how to solve it.

Termination and multiple LUNs come mind, but the cable provides termination and I don't see why a hard drive would request multiple LUNs, especially considering it is not jumpered at all, and multiple LUN support is disabled in the Adaptec's BIOS (via the SCSI-Select utility)

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I think I have found the problem. I changed the controller ID to 7 (from 6) and the HD only shows once now. However, it gets an ID of 6 for some reason (I was under the impression the default was 0, again it is unjumpered). I wouldn't mind it, but the windows 7 setup wouldn't load (hangs on the "Starting Windows" screen) and I suspect it has something to do with the ID not being 0 (it is purely a guess though)

EDIT - OK, it seems the factory default for the Maxtor Atlas is indeed ID 6 so my problems with the win7 setup must reside elsewhere, possibly with the card itself (setup doesn't hange with the AHA-2940U2B)

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Sounds strange to me, too. All the SCSI drive's I've owned default to 0 unjumpered. Is the drive the same ID on the 2940U2B as it is on the 2940UW? – hyperslug Jul 5 '10 at 12:57

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