I currently am setting up a computer for a relative. I want to re-use his old computer if possible, but I am not sure how well it will perform with Windows 7 Professional 64 bit. I plan to buy Windows 7 Professional OEM and set the computer up. After setting it up I would like to hand it back and ask my relative to test it. I'm not sure how well it will perform, because right now it's really slow and unresponsive while running Windows XP, and tons of malware. If setting it up freshly does not help performance-wise, I would like to dump the computer and build a completely new one. Now, the question is:
Will I be able to re-use the Windows 7 Professional OEM version?
Apologies if this question seems noobish, I've never actually bought a Windows version, except the ones that come pre-installed, which, on the other hand, I never used.