Business Application Performance - SCSI Hard Disk
By disabling the L2 cache I was able to emphasize the performance effects of the main memory. But I also thought it would be interesting to remove the onboard IDE controller from the picture also. I installed an Adaptec 2940UW SCSI adaptor and an IBM DVGS 9 GB 10,000 RPM SCSI drive into each platform. I wanted to put each platform at an equal level in the disk subsystem category. Doing this would rule out and mischievous IDE bus-mastering driver benchmarking tweaks. I figured this would also point out if any one of the platforms were lagging due to their IDE interface implementation.
Using SCSI really didn't change the performance deltas between any of the platforms. Even the i820's integrated UDMA66 didn't benefit the platform when using IDE.