Q: I've installed a new disk drive. But when I try to boot from it or mount it, I get an error message saying that unit is not found, or no such device.
A: Check the following:
VISUAL INSPECTION OF DRIVE:
1. Make sure there are three resistor terminator packs (yellow) near the 50-pin SCSI connector.
2. Make sure the jumpers on JP35, JP36, and JP37 (the SCSI Target Number jumpers) are set for Target 1: there should be a jumper on JP35, and NO jumper on JP36 and JP37. These are pairs of jumper pins that should be visible and should not have any blue jumper over them. These jumpers are used to select the SCSI ID.
INSTALLATION:
1. Connect DC power to the drive.
2. Connect the 50-pin ribbon cable to the CPU board and to the drive.
3. DO NOT connect the 20-pin connector on the end of the optical drive cable to the SCSI drive. It fits on some pins on the back of the SCSI drive, but of course, does not belong there.
POWER ON:
1. With the rear panel of the computer removed, power up the cube and immediately type cmd-` to get into the ROM Monitor.
2. With the fan disconnected it should be obvious whether the hard disk is spinning up or not.
3. After spinning up, the hard disk should make a barely-audible groaning noise. This is an initialization sequence of the heads.
CHECK SCSI COMMUNICATION:
1. Type "bsd" at the ROM Monitor "NeXT>" prompt and you should get some messages about the disk even if it does not have enough software to boot. You should at least see a "disk label" and it should identify the SCSI device as a 330 or 660MB hard disk.
Try booting or running BuildDisk or whatever your goal was again.
NOTE: see also the NextAnswers entry hardware.412.
