Improve PC Speed - Enable Direct Access Memory (DMA)

If you are not comfortable in understanding this inspite of below description, Please follow the steps as that would help you have a less load on CPU and which ultimately enables your system to work faster!

DMA:- Microsoft Windows includes a Bus Mastering feature known as Direct Memory Access or DMA. When this DMA feature is enabled, it basically allows your Hard Drive and CD Rom Drive to transfer their information directly to and from memory without passing through the Microprocessor.

In short, when your disk drives use Direct Memory Access to access their information, this reduces the load placed upon your Central Processor Unit (CPU) and therefore your system works faster.

Direct Memory Access (DMA) is the theoretical data access rate of a Drive measured in megabytes per second. Thus, an Ultra DMA-100 Hard Drive will theoretical access data at a rate of 100 megabytes per second and an Ultra DMA-133 Drive will theoretical access data at a rate of 133 megabytes per second. Therefore, this technical brief will show you how to enable Direct Memory Access (DMA) on your system.

Now follow the below steps to enable or Disable DMA. I have only provided for XP as for 98, you would need to enable both foe Harddrives and Optimal ones. Moreover I am concentrating on XP as 98 support has been officially stopped.


1. Right-click on My Computer, select Properties
2. Select the Hardware tab
3. Click the Device Manager button


4. Double-click IDE/ATAPI controllers
5. Double-click on the Primary IDE Channel

6. Click on the Advanced Settings tab (as shown in figure).The tab may or may not be
available for each option. It is only available in Primary and Secondary Channels.
7. Set the Transfer Mode to "DMA if Available" both for Device 1 and 0 and Click OK

8. Perform the same operation for other items in the list, if applicable.