Thought I'd share some interesting benchmark results. About a year ago the contents of my hard drive got trashed by the PCI read ahead problem. I found a replacement for IBM1S506.ADD written by Western Digital that boasted improved performance, so I gave it a try. This driver supports Block Mode PIO and DMA on Western Digital drives but not others. Using WDCIDEOS.ADD, the hard drive corruption disappeared and I've used it ever since.

Recently I was trialing the benchmark package, InfoPM 1.3 and decided to compare the performance of the WD driver, WDCIDEOS.ADD, to the latest IBM1S506.ADD dated 8/28/95. I'm running Warp Fullpack with Fixpack 10 installed. My system contains a 90mhz Pentium Intel PCI motherboard with the Neptune PCI chipset. Hard drive 0 is a Western Digital Cavier 730M IDE and hard drive 1 is an IBM Deskstar XP 1G IDE. Here are the results:

		Drive	Transfer Rate	Seek Time	Latency
		-------	----------------------	-----------------	-------------
IBM1S506	0	1574.84 kb/s	6.10 ms		8.50 ms
		1	2561.15	 kb/s	16.07 ms	0.78 ms

WDCIDEOS	0	3536.56 kb/s	8.20 ms		8.54 ms
		1	3111.15 kb/s	16.03 ms	1.53 ms

As you can see, even though DMA is not supported on the IBM drive, WDCIDEOS.ADD was able to improve its performance. Although the WD drive's specs are not as good as the IBM's, it outperforms the IBM drive when using the WD driver. I'm not sure why the IBM's seek time is so high since this drive is rated at 10 ms and the WD at 12 or 14 ms.

It would be nice if IBM came up with an OS/2 driver tuned to their Deskstar drives. I'll bet more performance could be squeezed out of this drive. How 'bout it IBM? 

WDCIDEOS.ADD does not support IDE CD-ROM drives. However, I believe  IBM1S506.ADD can coexist with WDCIDEOS.ADD. I can't verify this yet since my new Teac CD-56E 6X CD-ROM drive refuses to extend its tray and hasn't been tested yet. Its going back to CDW. However the CD-ROM drivers loaded successfully and the drive letter showed up. 

The WD driver is dated 10/05/93 and is at release 1.01 according to the readme. Its available in the OS/2 Device Driver Repository at ftp.europe.ibm.com. Although the repository version is dated 1/25/95, its the 10/05/93 version. The file name is WDEIDENV.ZIP but might be available elsewhere as the self-extracting WDCOS2.EXE. It doesn't seem to be here so I will upload it. Although it has worked flawlessly for me, use it at your own risk. Your mileage may vary. I'm not sure WD even supports it anymore since the only driver I could find at their Website was a version of IBM1S506.ADD dated 1/15/95.