UDMA Mode

Last Revised: 16 September 2008

DISCLAIMER:

NO LIABILITY FOR ANY PROBLEMS
ARISING FROM USE OF THIS PROCEDURE

** Use at YOUR OWN risk **

These instructions are for Windows XP.

If you have an earlier version,
the concept is much the same,
but the navigation is a little different.
eg DMA hangs off the drive rather than the controller.

I know nothing about later versions of Windows.

Check in Control Panel that you are NOT in PIO mode on any of your drives/controllers.

Control Panel - System - Hardware - Device Manager;

Expand IDE ATA/ATAPI Controllers;

double click on Primary IDE Channel click on Advanced Properties.

Check if Transfer Mode is set to "DMA if available".

If NOT then :-

Change it to DMA and click OK;
Restart the system;
and recheck the Current Transfer Mode;
Repeat for SECONDARY IDE controller.

If it was ALREADY set to DMA
but Current Transfer mode is PIO mode,
then Windows may have gotten itself confused.

If Windows persists in ignoring the "DMA if available" setting,
then to unconfuse Windows you may need to do the following :-

Uninstall the Secondary Controller in Device Manager;
Restart Windows;
Wait for Windows to detect and reinstall the drivers;
Change the desired Transfer Mode to "DMA if available" again;
Restart the system, and recheck the Current Transfer Mode.

"On a clear disk, you can seek forever" - Computerworld

DISCLAIMER:

NO LIABILITY FOR ANY PROBLEMS
ARISING FROM USE OF THIS PROCEDURE

** Use at YOUR OWN risk **