On Thursday, June 04, 1998 6:03 PM [log in to unmask] wrote: I am presently running one SCSI drive on my system and I want to add two more. When I added the first it boots to it and not my original drive. What I need to know is what determines which drive will be c: and which will be d:, e:. Thank you Richard Marcinkowski SCSI devices have device id assignments, usually accomplished by putting jumpers on appropriate pins. Some older SCSI adapters have BIOS that expect a certain ID to be bootable. The most common devices searched for bootable files are ID zero and one. You do not say which adapter you are using, but any late model Adaptec or similar adapter will allow you to enter the BIOS setup screen and designate the boot device. I usually set the boot device id to be 6, since device id has something to do with contentions, and 6 has higher priority than zero. If you don't have documentation, SCSI device assignments typically are binary values represented by individual pins, each pin being a power of 2. They usually are read right to left. (Turn this primitive schematic on its side!) * * = this pin is 1 * * = this pin is 2 * * = this pin is 4 * * = if the device is a wide SCSI or ultra SCSI, this pin is 8 Cover as many pins as you want to with jumpers, add the values of the covered pins, and this equals the device id. Don't assign a device the same id as the adapter, which usually is ID 7. Tom Turak tturak at ralgi dot com