3-20 Dell Dimension XPS Txxx and Txxxr Systems Reference and Troubleshooting Guide* 6 " : - $ &If you are installing an external SCSI device, connect one end of the external SCSIcable to the SCSI bus connector on the back of the device.For additional instructions on connecting SCSI devices, refer to “SCSI Cables andSCSI Termination” found earlier in this section.6. Attach the SCSI cable to the connector on the SCSI host adapter card.If you are installing an internal SCSI device, match the colored strip on the inter-nal SCSI cable to the pin-1 end of the 50-pin connector (for a narrow SCSI device)or the 68-pin connector (for a wide SCSI device) on the adapter card. Then pressthe cable connector firmly onto the adapter card connector.* 6 .. " : &If you are installing an external SCSI device, connect the other end of the externalSCSI cable to the external connector on the adapter card.For additional instructions, refer to the documentation that came with the adaptercard.7. Connect the SCSI device(s) to power.If you are installing an internal SCSI device, connect a DC power cable to thepower input connector on the SCSI device.If you are installing an external SCSI device, connect the socket end of the powercable to the AC power receptacle on the back of the SCSI device. Insert the otherend of the power cable into an electrical outlet.Check all other cable connections. Fold all internal cables out of the way to pro-vide airflow for the fan or cooling vents.8. Replace the front bezel as described earlier in “Removing and Replacing theBezel.”9. Replace the computer cover and support beam and tighten the cover-mountingthumbscrew.10. Reconnect your computer and devices to their power sources, and turn them on.11. If necessary, enter the system setup program and set Type to None for theappropriate IDE drive options. For instructions, refer to Appendix B, “SystemSetup Program.”Tape drives attached to a SCSI host adapter card are not part of the system setupprogram’s configuration information.