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03-22-2023 04:33 PM
Hi,
I just bought a Z840.
It has 128 GB of Memory, 8x16GB. It's a dual core.
Is it possible to upgrade this to 384GB, by adding 8x32GB ?
I looked at various places, to no avail. It's not confirmed but neither is it really denied.
Evert
03-22-2023 05:39 PM
Welcome to our HP User Forum!
The HP Z840 Workstation has 16 memory module slots. These slots are divided into two memory channels, with eight slots per channel. The Z840 uses DDR4 ECC Registered memory and supports a range of speeds, including 2133MHz, 2400MHz, and 2666MHz. The absolute maximum amount of RAM that could be installed in the system is 2.0TB (see: https://www.crucial.com/compatible-upgrade-for/hp---compaq/hp-z840-workstation), using 128GB memory modules in each slot -but I digress.
However, to answer your question, it is important to note that the documentation I found stressed that the Z840 requires a balanced memory configuration for optimal performance, so the memory modules should be installed in sets of four or eight.
When I researched this a bit more, this came up, and I quote:
"While it is technically possible to mix different sizes of RAM modules in a system, it is generally not recommended as it can cause stability issues and negatively impact performance. Mixing different capacity modules can lead to compatibility problems, and can sometimes result in the system only recognizing the amount of RAM that matches the smallest module in the mix.
In the case of the HP Z840 Workstation, it is recommended to use memory modules of the same capacity and speed to achieve the best performance and stability. It is also important to install the modules in sets of four or eight, as this ensures a balanced memory configuration across the memory channels. If you need to increase the amount of memory in your system, it is best to use identical memory modules of the same capacity and speed."
Hope this was helpful.
Kind Regards,
NonSequitur777
03-23-2023 01:36 AM - edited 03-23-2023 01:40 AM
the fastest supported ram speed is dependent on the installed CPU model, check the intel specs for your installed CPU's to see what the fastest speed they support 2133 is the baseline which all z840 compatible CPU's support
also note that many systems (including the z840) can have issues when adding more physical memory modules to a system this is due to the increased load each module places on the memory bus which is why a system may work fine with 4 no name dimms or different speed dimms but have issues when more dimms are added
if you are going to add that much ram, then I strongly recommend you visit the "crucial" web site or "Kingston" site and use the memory finder apps on each site to find modules that HP or the memory maker has qualified as supported for your z840 system
as a reminder, early AMD Ryzen based systems were very picky on memory and had issues if using non qualified dimms or more than 2 memory modules, the latest AM4 AM5 based systems are much more forgiving