Go to Control Panel> System> 'hardware' tab> 'device manager' button> expand 'IDE ATA/ATAPI controllers' branch. You need to know which channel (primary or secondary) your dvd player is on, right click on the appropriate channel> properties> 'advanced settings' tab. You can select 'DMA if available' there.
yeap, i also think so ..... now i changed the ide-chanels , so i can use the fast drive as a single on ide2 for the better speed an the dvd as slave on ide1 ... and it works .... but its a little silly (i have the latest via chipset drivers ... what can i do)
Last four digits are likely 0001, 0002. Under those keys you will find MasterIdDataChecksum, SlaveIdDataChecksum. Delete the value corresponding to your drive. It will make the OS to redetect the device DMA capabilities after reboot.
Check you BIOS - I couldn't even get an offer for DMA, until I checked in my BIOS and saw that the IDE Secondary Slave (were my DVD drive is), had UDMA "disabled" - so I enabled it and now it works great.