If you have a SCSI device that looses its' drive letter upon reboot, you may have the following configurations:
1. If you have Compaq SSD, get the latest one.
2. If your boot device is IDE
AND your SCSI device does NOT contain Windows NT
AND your SCSI device is configured for Boot in Control Panel / Devices
THEN change the SCSI device to Startup with System.
Assign the drive letter in Disk Administrator and reboot your computer.
See tip 522.
NOTE: - In Control Panel / Devices, you select the SCSI driver, such as AIC78xx for an Adaptec 2940 series adapter.
NOTE: - If your system boots from a SCSI device, don't try this.