Well, I certainly won't be installing SP3 on my main laptop until I've had a chance to check it first on the back-up!
Both Dells, so I hope that this AMD thing won't be a factor!
The AMD problem seems to stem from OEMs that have used their Intel XP images on their AMD machines.
This isn't the fault of Microsoft. It would work if the OEM used a separate image for their AMD machines, instead of being lazy and using one image for all.
Formerly working for an OEM myself, I'm all to aware of the problems a 'one size fits all' type of image can lead to.
That said, I've so far updated 5 custom built (by me) PC's with SP3, and all have been successful.