DMA is very important to DVD playback. What it allows your computer to do is, transfer data from a device to the memory without the use of the CPU. In our case, transfer Audio/Video data from the CD/DVD drive to the computer memory.

Without enabling DMA, the CPU has to transfer this data by itself, which slows down playback by up to 50%!

If you have an Intel LX or newer board, or basically any board with an AGP slot, then you can enable DMA support. To do this, you need to right click "My Computer", Select "Properties", Click on the "Device Manager" tab, open the "CDROM" branch, Select your DVD device, Press on the "Properties" button, Select the "Settings" tab and enable the "DMA" check box.

If you do not see a "DMA" check box, then it may mean you are running a board designed for AMD CPUs. These boards required a special driver to enable DMA and other bug fixes for Windows. You will need to get these from your motherboard manufacturer, or from the company that makes the chipset.

At times using these special drivers, it will automatically enable DMA, without the DMA check box being visible.

Also note, that under Windows 2000, the DMA option may be under the "Hard Disk Controllers" branch, rather than the actual DVD device.