Put both drives into the other PC and connect up both to same cable, just make sure that the drive with your operating system on is set as the Master and the other as slave. O/S disc will then be Drive c: and other drive Drive D:.
Settings could be by jumper settings on disc or by cable depending on type of disc
Some BIOS's require setting changes to recognise two discs.
Are they PATA or SATA drives?
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