RAM Issues: xw8400 and xw8600 workstations

[DBrunnenmeyer]

We're having issues with several of these workstations. When booting, some are reporting unusual "slot errors" usually confined to DIMM slots 1 and   2, but I'm told that on occasion, other slots are reported defective or some variation of that.

Question #1:  From what I can tell, the correct DIMMs are installed according to the information in the QuickSpecs for those two workstations, alhough in one case, I found 1GB and 2GB DIMMs in the same PC. I pulled the 1GB DIMMs and moved the 2GB  DIMMs to slots 1, 3, 5 and 7. After booting, a typical error message reads like this:

203-Memory Module failed self-test and falling rank was disabled.

Slot 1

                                                                          HP xw8400 workstation

The following configuration options were automatically updated:

  Memory: 6144 GB

Now one might think that this means that the DIMM in slot 1 is defective, Moving them around doesn't necessariy give the same result For example, rebooting the same setup gave a similar result but claiming a Slot 1 error but seeing only 4096GB.

Finally booting into Windows 10 (in this example), I found that of the 8GB installed, only 4GB was usable.

Is there a recommended way to test the DIMMs to see if one or more of them are really defective—like just installing one in Slot 1 or maybe two in Slots 1 and 5? What do you recommend?  Is something else getting into the act, like memory bank management on the motherboard?

Question #2:  Do the same memory slot recommendations in the QuickSpecs for these two models apply when the machine has only one processor instead of two?

I can do more testing and provide clearer examples of the errors we encounter on several of these machines,  but it seems my ability to solve these problems would benefit from some suggestions or information from one or more of the experts that contribute here. Thanks in advance for your comments. Lay it on me!

Dennis..

[DGroves]

you can try cleaning the menory modules contacts with Isopropyl Alcohol and if this does not help the module is most likely defective i have seen RDimms  (which run hot!! by nature) not show errors until they warm up

i have also seem memory modules that do not fit tightly in the memory socket and wiggling it in the socket might sometimes resolve the issue for a period of time

as to memory placement, follow the directions that are included on the side cover, and yes memory size and slot order is important the service manual should be downloaded for future reference

https://jp.ext.hp.com/lib/doc/manual/workstation/xw8400/364898-001.pdf

[DBrunnenmeyer]

It is understandable that over time, sockets and especiallyu ones that were not filled, could gather atmospeheric-borne contamination.

If the DIMM contacts are dirty, it's likely that the same is true of the sockets. Are there any recommendations for cleaning the latter without itntroducing further problems? Is it wise or unwise to apply dry compressed air to blow out debris?

I know tHat care should be taken to ensure that the DIMMs are fully seated, but is it possible to assert too much pressure and thereby damage the interface between the DIMM and socket or between the socket and the motherboard?

Are some after-market DIMMS known to be thinner than the ones with HP labels on them? Hopefully these machines are not notorious for having poor sockets or poor motherboard/socket interfaces.

I hope others will chime in and make suggestions or offer additional insight.

Thanks...   Dennis

[DBrunnenmeyer]

Does the number of processors installed (1 or 2) affect the number and/or the location of the slots that can or should be used for installing DIMMs?