I have a 2 TB external that has backups from 5 or 6 PCs. I used to use Norton Ghost, but since Symantec took it off the market, I use Easeus Todo Backup Free which is free for home use. Just don't use the Windows supplied backup; it's different in every release of Windows and it's buggy in some versions as well.
Good luck.
My old PC is no longer in use but I backed it up on my Maxtor Blackarmor 320GB.
I want to use the same Blackarmor for my second PC, and in fact without thinking about it I did a backup before remembering that I had already backed up the first PC.
First I have to figure out what to do with the current state of the backups, ideally separate them.
Then figure out how to put the first PC backup in it's own place. Then put future backups of the new PC in a separate place. Partitions?
XP Pro SP3

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