Ram disabled upon upgrade

[BernhardWilhelm]

Dear community, I just purchased a HP Z4 G4 with i9-10980XE. The machine comes with 2x 16GB dimms (description of machine on the web, no mods).

With the machine I purchased 2x HP 16GB (1x16GB) DDR4-2933 ECC RegRAM (recommended accessoire in the shop). I installed them as per the instructions that come shipped with it and are on the internet. However, the Dimms are not recognized. 

What I ruled/tried out so far:

- it is all 16 GB Dimms

- New Dimms are installed in slots 3 and 6 (black slots as described in the instruction), old dimms are in 1 and 8

- Dimms in different configurations didn't work, resulting in the usual beep

- Updated Bios as the Dimms are not reconigzed there.

- HP Performance analysis tool shows Dimms 3 and 6 are filled, however marked as "Samsung - DISABLED" while the other Dimms that work are listed as "16 GB Samsung"

Can anybody help?

[Prométhée · Accepted solution]

hi

have you tried the old modules in all slots one by one
then the new ones one by one in each slot

https://support.hp.com/us-en/product/hp-z4-g4-workstation/16449890/document/c05846113#AbT5

DDR4-2666 registered DIMMs

Only DDR4 DIMMs are supported.

Memory configurations using 32GB DIMMs require the HP Z4 Memory Cooling Solution, which is available both CTO and AMO.

[BernhardWilhelm]

Thanks for the help Promothee.

The specifications you sent are probably likely outdated as they are not even listing the CPU I got installed. The specifications however list only DDR4 memory up to 2666 MT/s data rate is supported. 

I tried the trial and error approach you recommended in terms of adding Dimm by Dimm. As it turns out that I can do this with the orginally shipped Dimms but NOT for the Dimms I purchased with the machine. 

I suspect as they are recognized as Dimms but disabled and the specifications don't list them as being supported that they are simply not. I will return these to HP. 

While very happy with the swift reply of you, Promothee, I'm pretty annoyed about HP selling incompatible Dimms as "accesoires" for their PCs.