Remove all of the cords and then both panels from your tower. You can find the screws on the back of your PC. Place the panels and screws to the side.
Remove your current hard drive. Pull the IDE cord, which is the thin, long cord out of the back. Then detach the white power cord connector. There may be two to four screws holding the hard drive in place.
Choose your master and slave drive. The master drive has the Windows operating system (in your case its your old 80GB drive). This drive should be the smaller GIG size of the two. Only Windows and Program files should run on this drive.
Change the jumper settings. On the back of both hard drives is a pin set with plastic connectors. The information regarding the jumper settings is on top of the hard drive. As all drives vary, you need to follow the instructions for your hard drive. Set the master and slave drives according to your decision in step 2. Push the jumpers into place with your fingers. Most drives these days also have a Cable Select jumper setting. You can also set both drives to cable select but that will require you to make sure you plug the drives on the right spot on the cable. (as discussed in step 5&6)
Screw the master hard drive back into the tower. Hook the IDE cable back into the long pin connector on the drive. Plug the white power cord in also. Push firmly as the connections are tight. Make sure you have them snugly into place before continuing.
Screw the slave drive into the tower near the master. There is a middle connector on the IDE cable; plug that into the slave drive. Take the second white power cord coming from the master hard drive and hook that into the slave.
Replace both panels of the tower. Then turn on the computer.
Hope that helps...
Dell Precision T7810, Win10 64bit fully updated, Symantec Endpoint Protection,
Watchguard Firewall, Intel Xeon E5-2620v4 CPUs, Dual 8 Core Processors, 32GB Ram,
E5-2620v4 @ 2.10GHz X 2, AMD FirePro W4100 with 4 Screens, 500GB SSD Boot Drive,
Raid-1 Dual 2TB Sata 10000 rpm Hard Drives, DVD Burner, IE11, Opera, MBAM, MBSB, MBAE