memory issues with HP X4000 Thunder i860 (S2603) motherboard

I have acquired an HP X4000 workstation which appears to use the Tyan
Thunder i860 S2603 motherboard with a 4 slot memory extension board.
The problem is that only certain RDRAM sticks seem to work in this
system (strangely enough they seem to be the HP branded memory). Other
PC800-45 ECC memory is either not recognized or in the case of the
Kensington memory shipped in the system, only 1/2 of the stated memory
size is seen (i.e. , a 256mb stick is seen only as a 128mb stick).
Internet searches have not been particularly fruitful, other than
finding a list of about 1/2 dozen recommended types on the Tyan website.
Since I was always under the impression that one PC800 ECC RDRAM stick
was the same as any other, I am a bit puzzled. Can anyone reduce my
state of ignorance here?

 

Hi, I built a Maya Animation workstation with this Tyan S2603 Thunder, Motherboard. I have now had it for 6 years, it has been performing flawlessly.

I think I can shed some light on your ram situation.

1. The memory recommended by Tyan, and as a first time builder, I had worked closely with their tech support to guarantee my success of the the build;

The ram I purchased, called RDRAM which I have had no problems with: It Is: Samsung Original Pc800 ECC 512mb 184Pin RDRAM sticks.

This board has 8 RDRAM slots. If all 8 slots aren't filled, (meaning if you have less than 8 sticks of RDRAM), the ram you want to install has to be installed in a very specific order, and (C-Rimm Modules, or C-Rimms, (short of Continuity RIMMS), are used to go into the remaining, empty slots. They fill these empty slots, in a very specific order, according to a specific Diagram Map.

I have this diagram map from their Motherboard book that will show you how to install different RDRAM configurations in the proper order.

If you don't have 8 sticks, and want to install less, you need to fill the empty RDRAM slots with these C-RIMMS. If they aren't installed properly, and according to the diagram map, YOU WILL HAVE PROBLEMS.

What you described sounds to me like that might be the issue.

For more detail and information feel free to
email me at:


I can also send you a pdf file of the Motherboard Manual and Diagram Map of the RDRAM configuration. Tyan's Tech Support, I have found to be amongst the best.

I love this motherboard and I have built a faithful, reliable system around it.

Also feel free to call me, at 516-285-1467 as well.

I think I can set you straight on this.


sincerely,
Michael Breskin
michebre