Compaq 159715-002 - Deskpro EN - DT 6650 Model 10000 Configuration Manual page 136

Cabling for Optional SCSI Devices
C-4 Hard Drive Installation Guidelines
Depending on the model, your computer may include one of the
SCSI cables shown in the next illustration.
SCSI Cable Options
Because your computer comes preconfigured, cable
configuration does not become a consideration until you decide
to add an optional SCSI device.
1 Computers with 2-peripheral SCSI cables (without
termination) must have termination enabled on the last
device.
2 Computers with 3- and 4-peripheral SCSI cables come with a
terminator 3 on the end of the cable. The connector on the
opposite end of the cable always connects to the system
board. All SCSI devices connected with these cables must
have their termination disabled.
Some devices may not have terminating jumpers on the
device. Termination on these devices must be achieved
with terminated cable.