Maximum memory per slot for Z420 v2 ?

[KwadGuy]

There was a cool post a while ago about how someone was able to get their Z420 running with 256 GB of memory by using 32GbB LRDIMMs. I was all ready to buy a bunch of these and then found a follow-up post indicating that this only works in a Z420 v1 workstation. The Z420 v2 motherboard removed support for LRDIMMs. 

The part number that works for the v1 workstation is:  712384-081

My question is: Is there a 32GB DIMM that works for the v2 Z420? If so, does anyone have the HP part number that workis?
If not 32Gb, then at least 16GB that works with the Z420 v2? 

[banhien]

@KwadGuy 

It can use 8 x ECC Registered DIMM Slots accepting up to 128GB RAM (8GB x 16), 1866MHz MT/s as mentioned on the following pecs

           https://www.bargainhardware.co.uk/hp-z420-v2-workstation-configure-to-order

Regards.

[KwadGuy]

Thanks..

Does anyone have an HP part number for the 16 GB RAM sticks that are verified to work in a z420?

[SDH]

The info above is a bit off.

8GB x 16 is incorrect. There are only 8 total memory slots. 16GB x 8 will work. The official word from HP is that they want you to use ECC unbuffered in the Z420 but ECC buffered works fine too, and that is what retired server memory usually is so you can find great deals using knowledge and eBay recycling. I've posted in the past on exactly what 8GB and 16GB sticks to use. You can look up my prior posts on this in this forum.

With that much memory you need to pay attention to case cooling. Turns out you can use the Z440 double cooling capacity processor heatsink/fan in the Z420. That helps cooling overall. There is a Z420 air baffle that directs cooling airflow to the front memory bank and then up and out via the power supply. There is a front case cooling fan that you need if you don't already have that.

1866 MHz memory is the stuff to get but that benefits you only if you have a processor that can also run at that speed. A fast processor will be held back by slow memory and vice versa.

Regarding the "L" memory... that defaults to normal power use rather than L-level power use because these workstations can't use the L value. So you'll not get any carbon credits if you spend extra for that.