The HP/AMD Patch Worked Fine On About 20 Comps Here
At the time when SP3 first came out, I performed the updates on quite a few Windows XP machines with a fair number of them being HP/AMD (old) machines.. Installation of the fix/patch worked fine and all machines installed SP3 perfectly.. Of course, we did the SP3 update shortly after it first came out and prepare each of the computers by performing all of the steps in the link below.. (Preparation is the key to getting a clean install.)
Update: Preparing Your Windows XP Computer For SP3
I installed SP3 on over 100 machines and had ZERO problems but all machines were prepared as per the link.. Any malware or hinky programs were REMOVED before the service pack was installed.
Hope this helps.