This may sound really weird, but I have a Sis controller
and it worked for me. All I did (In device manager)
And "Properties" of my (Pri IDE channel), was change the
setting from "DMA if available" to "PIO only", click OK-
Then change it back to "DMA if available" and click OK
again. All the sudden it enabled my DMA which XP had
decided to disable. No restart or anything. Don't ask me
why. Your right, PIO sucks- My computer ran like crap
until I stumbled on to this. Again, I can't imagine how
something so simple worked, but it did- Good luck
