To enable or disable PIO/DMA modes simply follow these steps:
Open Device Manager: Start - Run - DevMgmt.msc
Expand the category "IDE ATA/ATAPI Controllers"
Right click the desired IDE controller (Primary/Secondary) and choose Properties.
Choose the "Advanced Settings" tab.
Change "Transfer Mode" as necessary.
Note: This option will only be available on hardware that supports this feature. If you are unsure please contact your hardware manufacturer.