Enableing DMA Mode

I recently purchased a 16x\48x DVD-ROM drive. I noticed that it was running slow, so I ran a system test to see how fast this compared to my old one. The results showed that the average CD read speed was 18x. The program said it was opertaing slow because it was running in PIO mode and said to enable DMA to make it run faster and use less CPU power. I can't figure out how to do this. I messed around in control panle and in the DVD-ROM properties but I still can't figure it out. Any help?

Assuming you run Windows Xp Go to Control Panel/System/Hardware/Device Manager/
Hit the + next to IDE ATA/ATAPI controllers double click on your primary or secondary IDE Channel(do both, one after the other), go to Advanced Settings tab, under transfer mode select "DMA if available" for both device 0 and device 1

Im running Windows 2000 Pro, but I figured it out. Doth primary and secondary both were running in DMA and Ultra DMA mode already, but my drive is still preforming poorly. Are there any more things I can do to try to increase my DVD-ROMs drive preformance?

Maybe you need to enable the DMA in the BIOS for the IDE channels too?

And the CD read speed of 18x is quite normal if it's not a relatively new CD from a factory.