So finally Windows has SATA drivers baked in. I've been told that not all chipsets are supported but many are. Mine is a VIA 8237 and RC1 installs just fine without loading any OEM drivers at install time.
The problem is that the drivers for my system were causing terrible stuttering and skipping the audio. It as also causing the mouse to skip sporadically. A little research shows that lots of folks have been having this issue so I think it reaches beyond VIA 8237 systems.
A quick update of the SATA drivers to the XP64 drivers from my board's manufacturer's website and all was smooth again.