ServerWorks HEsl: DDR bandwidth without DDR SDRAM

Poor AGP performance

The second issue we ran into was that the graphics performance of the HEsl chipset. Using our test bed's GeForce2 GTS, the HEsl platform was over 40% slower than the rest of the test setups. We also found it odd that there were no AGP drivers present anywhere, either from ServerWorks or the motherboard manufacturers that used their chipsets.

It turns out that in order for the OS to properly recognize the HEsl's AGP bus you've got to fool it into thinking the North Bridge is actually an LE chip. ServerWorks was kind enough to send us instructions on how to do this, have a look at them first:

1.      Program the following registers in Function 0 of the chipset.

(a)    Set the bit “7” of Index “5B” to One.
(b)   Set bits 3:0 of Index “5B” to 0111h.
(c) Read the Index “02” to know bits are set (it must read 0x07).

2.      Program the following registers in Function 1 of the chipset.

(a) Set the bit “3” of Index “48” to One.
(b) Set bits 3:0 of Index “C7” to 0101h.
(c)    Read the Index “02” to know bits are set (it must read 0x05).

3.Implement Vendor ID and Sub System ID in Index 2C,2D,2E ,2F (Function 1)

(a)    Set the bit “3” of Index “48” to One.
(b)   Set the Index “C8 – C9” to reflect your Vendor ID.
(c)    Set the Index “CA – CB” to reflect your Sub System Vendor ID.
(d)   Index “2C – 2F” reads the value written in Index “C8 – CB”.

Now aren't you glad that VIA puts regularly updated INF patches and AGP GART drivers on their website? In order to give the HEsl a fair chance we contacted ServerWorks and worked with them to find the best method to go about fixing this issue.

They managed to produce some assembly code that we could run which would change the chip id for the North Bridge, which should enable proper AGP support by Windows 2000. Unfortunately, after multiple reinstalls as well as mucking around with the test board's BIOS our efforts were fruitless.

The assembly code managed to get the chip id changed and the AGP bridge to be recognized, however installing NVIDIA's Detonator drivers resulted in a black screen upon booting to Windows 2000 every time.

This is another major disappointment since there should be no reason that ServerWorks can't do what ALi, Intel, SiS and VIA all do in order to provide proper support for their chipsets under Windows 2000: release a driver/INF patch.

As it stands now, you pretty much have to deal with the poor graphics performance of the solution. How bad is it? Take a look at the SPECviewperf performance numbers we produced:

ServerWorks believes that there is a solution to this, why it hasn't been implemented in the current motherboard designs or in the form of a driver patch is beyond our understanding however.