Yes. Here's why. If it's Windows XP, the activation alone will try to activate again plus minor hardware differences will cause the drive and the OS to not boot.
Why not move your stuff over with your backup?
You do backup, don't you?
Bob
PS. Another nifty thing is that XP has a nasty habit of rewriting the partition table on a drive you add to some system. I've seen and read posts here where people panic when they put the drive back and the slave on that system vanishes (along with the data they didn't backup.)
I have a DELL Dimension 4600 series, and am about to purchase a 4700 series (has a different processor, chipset, ram, pretty much everything). In order to preserve my data and restore the 4600 series to its original state, I was just going to physicall switch hard drives on the two pc's. Would this cause any problems (ie. BIOS issues)?
Would the computer recognize all of the changes to the system and make the appropriate adjustments?

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