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- HP Z800 sudden memory error

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01-19-2023 07:38 PM - edited 01-19-2023 07:40 PM
Hello people!
I have a old HP Z800 that was working nice and reliably. I was streaming movies to my TV this weekend and it was working fine, then i shut the machine down to go to dinner. Then i powered up the machine and the hell stated. It was beeping 5 times, which according to the user manual, means pre-video memory error. I rebooted the system and it says, after loading the SAS ROM, the folowing error:
209-Memory warning condition (WARN_DIMM_VREF_NOT_PRESENT) detected slot CPU0 DIMM6.
Whats strange about it is: slot 6 either in CPU0 and CPU1 aren't in use, they're empty.
OK. i press F1 to boot and the system works fine. Yesterday night i thought it would be a good idea to took the system apart and try to find the error. Now the system condition is COMPLETELY random: sometimes it boots without errors and work fine, sometimes it boots fine but with error 209, sometimes the bios post beep is delayed a hell lot and the monitor turns on with a blinking cursor and nothing more, sometimes the 5 beeps appears.
What i notice is whenever i remove the memory sticks from the CPU1(memory slots only filled in CPU0), the system works, but with the 209 error code. I tested each memory stick independently.
Machine specs:
HP Z800
2x Xeon X5675
GTX 980
4x Samsung M393B2K70CM0-CF8 PC3-8500F 1066MHz (16GB each, 64GB total, 32GB local memory per CPU)
The memory sticks are in this configuration;
CPU0 SLOT DIMM1 and DIMM3
CPU1 SLOT DIMM1 and DIMM3
I tried two Xeon X5650 too, same problem.
Sorry for my english, and thank you for helping me!
01-20-2023 11:01 AM - edited 01-20-2023 11:05 AM
the z800 uses groups of 3 dimms for each memory bank, with EACH CPU REQUIRING RAM TO BE INSTALLED
ram dimms in each CPU memory bank must match what is installed in the other cpu bank for best performance
follow the dimm load order that's printed on the inside of the side panel, or use the link below
https://h20331.www2.hp.com/Hpsub/downloads/Mini_WP_Z800_memory.pdf
if the proper load order does not resolve the issue
the dimms could be bad ,swap modules between cpu banks in groups of three and note if errors move between cpu
bent pins on the cpu socket(s) the memory controller in in the cpu itself
some pci-e cards require covering the "SM" bus pins or you will get random memory errors, but your description does not mention you adding any pci-e cards so i doubt this is the issue, but removing all cards except for video and testing will rule out a failed pci-e card
failed motherboard , it's possible the board has failed, test the above things first
01-20-2023 02:58 PM - edited 01-20-2023 03:00 PM
Hello!
The DIMMs are correctly placed. I also tried every configuration possible and tested each stick individually.
This morning the system booted without any errors. But now its throwing this 209 error again.
I know the memory controller is in the cpu itself, so i suspected it could be a cpu failure. I tested another working one and the problem persisted. Already checked the socket for bent pins and all was straight.
What's strange is once the system boots, even with 209 errors, everything works fine, no crashes, no slowdowns, no unusable memory, everything works.
It's tricky to make it boot. Have to remove power cord from PSU and wait for the capacitors to discharge. Try again, maybe again again, and it works the second or third try.
Thanks!
01-20-2023 04:35 PM - edited 01-20-2023 04:53 PM
all memory in a bank must match, make sure that the dimm module(s) ranks are the same common ranks are 1/2/4
https://www.crucial.com/support/articles-faq-memory/what-is-a-memory-rank
hp error 209 is a memory configuration error, you have a system with memory modules in the wrong slot/ wrong rank/ wrong speed/ or non registered dimm module or a wrong bios setting
as i recall there is a setting in my servers the BIOS called "Advanced Memory Protection" (or AMP) and if the DIMMs don't support the mode selected you get this error.
set the bios to factory defaults save then power down and only install one bank of dimms for each cpu (6 dimms total)
if still 209 error post pics of thes 6 dimms, and try the remaining 6 dimms
you can also have unregistered ECC ram or unbuffered ram
the z800 requires the ram be registered and buffered
please list the module maker and the size and timings and the rank of all your dimms
again, refer to the memory config link i linked to previously
01-20-2023 05:05 PM
Hello
The dimms are all registered buffered quad rank ecc, see the machine specs in my original post
I tried resetting the BIOS. The problem isn't persistent, it's completely random.
I have 4 identical dimms, tested every combination possible in the system. The memory works fine and no errors reported.
I think it's a mainboard fault
Thanks
01-20-2023 05:12 PM - edited 01-20-2023 05:13 PM
your post stating dimms in banks 1 and 3 IS A IMPROPER CONFIGURATION AS I STATED
PROPER CONFIG IS DIMM SLOTS 1/3/5 POPULATED FOR EACH CPU (TOTAL 6 SIX16 MEG DIMMS)
the z800 uses groups of 3 dimms for each memory bank, with EACH CPU REQUIRING RAM TO BE INSTALLED
your current config of only 2 dimms per bank is INCORRECT
LAST TIME, REFER TO THE MEMORY CONFIGURATION PAGE I PREVIOUSLY LINKED TO