|Begin by taking the 80gb drive out and connect only the 500g drive.|
Setting the jumpers should not be an issue at this stage as the 500 was most likely configured as master in the system it originally came from.
Now boot up into BIOS setup and check for drive detection and set the boot order to CD first followed by hard drive.
I gather there is a 65gb partition on the 500g drive that you wish to install a fresh copy of XP. Was that the partition that originally contained XP when the drive was in it's original machine? If you need help installing XP there are guides available in the HowTo forum.
Once you get XP up and running on that drive you can then deal with the 80g drive. There is usually a diagram on the back of the drive to show you how to configure the jumper to make it master/slave, How you configure it will depend on whether you place it on the same cable as the 500g disk or the secondary IDE cable, as well as the settings of the other device that shares the cable EG: optic drives.
Each cable can accommodate two devices with one set as master and other as slave or with both set to Cable-Select (not recommended in my opinion).
If you only have one optic drive I would put the 500g drive alone on primary IDE as Master and then put the 80g and optic drives on the secondary IDE with the HDD set as master and optic as slave.
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