I have an Adaptec 19160 and an IBM DDYS-T1835ON 18 gig U160 HD. I was attempting to install linux on my Acorp 6815EPD.
The initial install of Red Hat 7.3 hung while loading the aic7xxx SCSI drivers. When I rebooted, the Adaptec Bios when scanning the SCSI ID of the IBM HD reported: "ASYN - Start Unit Request Failed". I could hear the HD platters spinning.

I was able to access the SCSI bios. I attempted to verify the IBM HD media and then format it. Both attempts failed with errors indicating that the target was not ready. I checked the connection and termination. Both appear to be in order. I would appreciate any advice. Is my HD dead or does the Adaptec need to be replaced? I've had both of these devices paired for almost a year without any trouble.

I doubt it's the controller.
My money is on a dead drive. While the platters may be spinning the command that the HBA sends to the unit doesn't just mean to start in the literal sense ... the drive is not "home" and taking no calls.

If you have data on the drive ... and another like HD ... a logic board swap could get it up and running. Otherwise, it's RMA time.

Sorry for your loss.

Thanks for the reply. I secured an RMA from IBM and shipped the drive off this evening. Fortunately, I had just formatted the drive for a clean install of Linux so no data was lost. Unfortunately, I have to have this box up and running for school (which begins next week), so I purchased a Fujitsu MAN3184MP from Newegg as an interim drive. It was cheaper than the Atlas III that's in my existing rig and comparable performance wise.