Are you saying, Hurn, that if my machine is an AMD based self-build with XP Pro installed by me from XP CDRom I
should be OK?
Well, I have installed SP3 on my own AMD X2 3800+ system which was self built and had Windows installed from scratch and it worked just fine.
No problems whatsoever, so yes you should be ok.
However, with any major upgrade, you should always have your data backed up just in case.