On the X5DA8, is the 50-pin SCSI channel independent from the two Ultra320 channels? If I use the 50-pin SCSI connector, will that degrade one of the Ultra320 channels?
Yes, the 50-pin SCSI connector is independent but the bandwidth ties with the Ultra230 SCSI controller on channel B. If you have both 68-pin SCSI devices connected along with a 50-pin SCSI device such as tape backup, the performance on the 68-pin channel B will be downgraded to that of the tape backup.