This page is being set up because of ridiculous difficulty I experienced when I purchased a new Western Digital 250GB hard disk for my system (1.4Ghz Athlon, Asus A7A266).

After scouring the net, I came to realize that I was not alone. The problem expresses itself in a number of different ways. If most or some of the following seems to apply to you, I hope this page can be of assistance:

1. You are running a motherboard using ALiMagik 1 chipset, such as the Asus A7A266, or Asus A7A266-E.
2. Your harddrive is a 'large disk' > 137GB, and the BIOS does not properly detect the capacity of the drive.
3. You are experiencing poor performance with your large disk.
a) Windows forces you to use PIO for your large disk. In Win2K and WinXP, this is caused by multiple DMA timeouts on startup.
b) Other OSes (such as Linux) report DMA errors, or many CRC checksum errors when using DMA.
4. Often, other drives (same or different IDE channel) will run properly in Ultra DMA mode, while the large drive will not.

Here are a bunch of files that will help you in trying to get your large disk to work properly:

1. asusupdt52301.zip - Latest version (as of 1/19/2004) of ASUS Update software, used to flash your Asus motherboard BIOS.
2. 1013-001.zip - Asus A7A266 BIOS 1013 Revision 1. Large disk (> 137GB) support is available from 1011 on, according to Asus' website. However, I found that my 250GB drive would not be properly detected in the BIOS with any BIOS earlier than this.
3. wdc_cfg.zip - Western Digital's firmware flasher. This allows you to update the firmware of Western Digital drives located on the PRIMARY IDE CHANNEL ONLY. Included in the zip file is a README, and a DOS-executable.
4. alimagik_drv104.exe - ALi's Integrated Driver, v1.04. Includes updates to the mini-IDE driver, and updates to the AGP miniport. If you are having problems enabling DMA for your disk on WinXP+SP1, you might want to try the beta version.
5. ali_integrated1.091.exe - ALi's Integrated Driver, beta v1.091. Note -- this driver will force Windows to re-detect your Master IDE Controller. This is the primary cause for the DMA conflicts described above. The default Ali M5229 will be replaced by 'ALi Ultra IDE Controller'. In my case, both my ATA drives were subsequently classified as SCSI (since ALi's driver is detected as a SCSI/RAID controller) -- however they functioned perfectly fine. If you have the A7A266 (or other ALiMagik 1 chipset based board) then do NOT run the newer integrated drivers that you might find on ALi's website -- they cause the IDE Controller to no longer respond to Windows.


UPDATE!!!
6. IDE4008.exe - ALi's UltraIDE driver, version 4.0.0.8. The Integrated Driver above (1.091) has UltraIDE driver 4.0.0.7. Directly from the README.TXT for this file:
This file contains a variety of information you should read before installing ALi Ultra IDE driver. ALi Ultra IDE driver is a driver for NT5 Architecture (e.g., Windows 2000 and XP). It supports hard drive which has size larger than 128GB (1G=2 ^ 30). It also supports ATA133 hard drive for better disk performance (ALi M1535+, 1535D+ chips support ATA133 feature).
In other words... large drives NEED to use ALi's UltraIDE driver, and NOT the mini-IDE driver that is found in other versions of ALi's Integrated driver.

Helpful links:

The preceding files and information were collected from the following websites:

1. ASUSTeK Computer Inc. - Support
2. ALi Corporation - Support
3. Western Digital Corporation - Software Library
4. DMA Mode for ATA/ATAPI Devices in Windows XP - this explains how Windows XP deals with DMA mode devices
5. Microsoft Knowledge Base Article 817472 - IDE ATA and ATAPI Disks Use PIO Mode After Multiple Time-Out or CRC Errors Occur - this article details a known WinXP issue that causes disks to be forced to PIO instead of DMA. If your computer seems to have DMA errors despite what OS you are using (to do a test run, try running Knoppix, a Linux Live on CD) then this article is probably not helpful for you. However, if your drive seems to only have a problem when you are using WindowsXP, then contact Microsoft for the patch, and follow the directions provided to update your registry.

Contact Info
At this time, please do not contact me for further help or support. All I know, I have put on this humble page.