Enabling UDMA Bus Mastering
So how do you get this so-called Bus Mastering to work anyhow? First, let's make sure your ducks are in a row. You must have the following squared away:

1) A mother board with the proper chip set for bus mastering. The 430 FX, HX, VX, TX and 440 FX, LX, EX, BX, GX chipsets from Intel will support UDMA bus mastering as well as the VIA chip set and some other competing chip sets.

2) A disk drive that is Ultra DMA compliant. Most new drives are.

3) Windows 98, Windows 95 OSR2 or above, or Windows NT with service pack 3 (at least!) installed. How can you tell if you have this condition met? If you have Windows 98 installed, you're ready to rock. If you are running Windows NT and don't know if you have service pack 3 installed, then you aren't the one to be messing with NT and you need to call in whoever it is that normally administers your system. If that's you and you still don't know what I'm talking about, sell your system and buy a Windows 98 system. You'll be better off. Otherwise, NT users please skip ahead to section 6) below. Windows 2000 users can skip to step 7).

For those of you still running Windows 95, open Control Panel and double click on the SYSTEM icon. You will see a box with the Windows logo and a heading "System" beside it. The system will shows "Microsoft Windows 95" on one line. If you see "4.00.950b" or "4.00.950c" on the second line, you're good to go. If you see "4.00.950" or "4.00.950a" on the second line, then you should upgrade to OSR2 or OSR 2.5 or Windows 98. If you're stubborn, you can also download the Intel bus master driver for your version of Windows 95 from Intel at:

http://developer.intel.com/design/chipsets/drivers/busmastr/index.htm

However, there's a catch! If you install this driver and later upgrade to Windows 98, you MUST un-install this driver prior to the upgrade. This driver was never meant for Windows 98 and your system will likely go nuts if you leave this driver in place. If the driver is already on your system and you are going to upgrade to Windows 98, you can download the driver install program and use it to un-install the driver first, then do the upgrade.

4) Now you need to see if Windows has properly identified your mother board chip set. You may need to run the Windows 95/98 INF Update utility. To see if you do, you must first know the chip set on your mother board. Get out the book that came with it and see what it says. Next, open CONTROL PANEL and double click on the SYSTEM icon to get the box with your system version number. Now look at the following chart to see of you need to even go any further with this process.

	Operating System
Chip Set	4.00.950	4.00.950a	4.00.950b	4.00.950c	4.10.1998
430FX	NO	NO	NO	NO	NO
430VX	YES	YES	NO	NO	NO
430HX	YES	YES	NO	NO	NO
440FX	YES	YES	YES	YES	NO
430TX	YES	YES	YES	YES	NO
440LX/BX/EX	YES	YES	YES	YES	NO
440GX	YES	YES	YES	YES	YES

Table taken from Intel document,
"Troubleshooting Common System Configuration Issues"

and that's it, well, you need to run this utility. You can get it from:

http://developer.intel.com/design/software/drivers/platform/440.htm

Be sure to read everything there including the README text to make sure you know what's going on.

5) Open CONTROL PANEL and double click on the SYSTEM icon. Select the Device Manager tab and then click on the "+" box next to "Disk Drives" to expand the list of hard drives on your system. Double click on the first IDE disk entry in the list. You will get a new control box related to that drive. Click on the "Settings" tab. You should see a check box labeled "DMA" in the center of the right side. If this box is grayed out, you have some troubleshooting to do. If it's not grayed out, check the box and then click OK at the bottom. Now double click on the next IDE entry if you have more than one IDE drive. Do the same thing for this one and any other ones you have. Click on the "+" box for your CD ROM also and follow the same procedure. If your CD ROM is UDMA compliant, you will have a DMA check box for it (them) as well. Check these boxes also. Now all of your drives will be running bus mastering once you reboot.

6) To activate bus mastering on Windows NT, you must run a utility called DMACHECK.EXE in the support\utils\i386 directory. If it's not there, download it from:

http://support.microsoft.com/support/kb/articles/Q191/7/74.asp

Run DMACHECK and it will show you if DMA is enabled on either IDE channel. If not, click on the ENABLE radio button for all of the DMA compatible devices on your system that you wish to activate. This should be all of your hard drives and any CD ROM drives too. Any other listed devices, well, that's up to you. After the selections are made, reboot and run the program again. It should tell you that all of the devices you selected are now enabled for DMA protocol. If this operation failed, there's some good advice from the web. Go to:

http://www.arstechnica.com/tweak/nt/udma.html

Be prepared to do some registry hacking! It may come to that. At least this document will give you a fighting chance, so check it out even if you don't think anything went wrong. You may have been fooled by DMACHECK!

Users of Windows 2000 have an easy time of it. Bus mastering is installed and activated by default so you need do nothing to use it.

7) Now it's time to run a benchmark test that will focus on your system's performance under DAW conditions. Jos� has written a benchmark test that accurately simulates multi-track digital audio streaming called DSKBENCH.EXE which can be downloaded from Jos�'s corporate web site:

http://www.SESA.es/

Click on the "Downloads" link in the index frame to locate it. This program is run from a DOS shell and will report record and play throughput in MB/sec as well as an estimated number of audio tracks you might expect to be able to stream simultaneously with that drive under real conditions. For details on using that benchmark, continue to the section DAW Disk Benchmark (To be posted in the very near future).