Go to the device manager (start => run => devmgmt.msc),
expand IDE ATA/ATAPI controllers,
double-click each IDE channel,
go to advanced settings and check that the transfer mode is set to "DMA if available" for all the devices.
If it reverts to PIO mode automatically then uninstall that IDE channel (right-click => uninstall),
reboot and Windows will redetect and reinstall it automatically.
If it still reverts to PIO after that then report here,
there'll be some values to change in the registry.