Primary IDE channel works fine. Both my 100gb Western Digital and my 60gb are set to Ultra DMA My secondary IDE channel has two CD-Roms. A plextor 24x cdrw and a sony 52x cdrom. Both cdroms are set to run in DMA when it is available, but they are both currently running in PIO. I am running win2k and have all the latest drivers and updates for every component in my computer.