ServerWorks HEsl: DDR bandwidth without DDR SDRAM

Don’t count on IDE

Things weren't perfect with our HEsl experience unfortunately, in fact there were a handful of issues that we would not have expected from a server class solution like this.

The first time we ran through the HEsl's performance tests we used our usual chipset test bed, which made use of an Ultra ATA/100 IBM 75GXP drive. Realistically, HEsl purchasers will most likely be pairing up their boards with some sort of high-speed SCSI solution however for our purposes we just wanted to compare it to other platforms not necessarily construct a server out of it.

With the 75GXP we noticed that the HEsl platform was performing quite poorly even to the point where it was being outperformed by a dual Apollo Pro 133A based system. After running some IDE performance tests on the platform we noticed a very unusual anomaly, the 75GXP was bursting at 16.5MB/s. This is even slower than the PIO Mode 4 specification allowed for (this was prior to ATA/33 if you remember).

We asked ServerWorks about it and learned some very interesting information. It turns out that the HEsl's South Bridge isn't even ATA/66 compliant, it only offers ATA/33 support and even then the performance of it is quite poor indeed offering burst speeds at barely above half of the ATA/33 specification.

This wasn't a problem for us; we just switched to the Seagate Cheetah X15 as our test drive. For those of you that aren't familiar with it, the X15 is a 15,000 RPM Ultra160 SCSI drive and calling it fast is definitely an understatement. But you should be very weary of using an IDE drive on any ServerSet III chipset (they all use the same South Bridge) if you're going to be using it for anything more than just a boot drive. This shouldn't be too difficult of a problem to fix with some driver workarounds, but it is a disappointment that it does exist.