Dell Dimension 3000 - Manual (Page 22)

4. After the drive is in place, apply pressure to ensure that the drive is fully seated.
5. Use the securing screw that came with the drive to attach the drive to the computer.
6. Connect the power cable to the system board .
7. Locate the data cable from the CD or DVD drive in the upper drive bay and connect its middle data connector to the new drive.
8. Reattach the front panel .
9. Replace the computer cover .
10. Connect your computer and devices to electrical outlets, and then turn them on.
11. See the documentation that came with the drive for instructions on installing any software required for drive operation.
Processor
Removing the Processor
NOTICE: Match the colored strip on the cable with pin 1 on the drive (pin 1 is marked as "1").
NOTICE: To connect a network cable, first plug the cable into the network wall jack and then plug it into the computer.
NOTICE: Do not perform the following steps unless you are familiar with hardware removal and replacement. Performing these steps incorrectly could
damage your system board. For technical service, see "Contacting Dell" in the Owner's Manual.