Dell OptiPlex GX620 - Manual (Page 159)

4. Connect the power and hard-drive cables to the drive.
5. Check all connectors to be certain that they are properly cabled and firmly seated.
6. Gently position the drive until it clicks into place.
7. Check all connectors to be certain that they are properly cabled and firmly seated.
8. Replace the computer cover .
1 drive
2 release tabs (2)
3 hard drive bracket
1 power cable
2 serial ATA data cable
1 release tabs (2)
2 hard drive