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Can someone please confirm memory compatibility for HP Z420 v2?

HP Recommended
HP Z420 v2 - E5 1650 v2 Proc.
Microsoft Windows 10 (64-bit)

Hello HP community & staff,


I need to upgrade my HP Z420 v2 workstation to the top spec of 64 GB 1866MHZ DDR3 RAM.

Can someone please confirm the following memory is compatible with the HP Z420 v2 mainboard?

CPU is the Xeon E5 1650 v2, PSU is 600 watt option:


Hynix 64GB 8X8GB PC3-14900E 2Rx8 DDR3-1866MHZ ECC Unbuffered 


Its my understanding that the HP Z420 v2 requires ECC Unbuffered, I just need confirmation because I just found ECC Registered RAM in a Z420 v1 I have laying around that works fine and want to be sure I'm purchasing the right RAM for my v2.

I really appreciate the help in advance.




Edit: Found this great article explaining ECC registered vs unregistered:

ECC Registered vs Unregistered - Serve the Home 

Also found out from the forums here that the HP Z420 does indeed work with both ECC registered & unregistered/unbuffered (I can also prove that as I have a Z420 running with 32gb registered).

From the article though seems as though unregistered would be the way to go for the Z420, seeing how its a performance-oriented system I don't think you'd want that extra hop between the CPU and Memory. Probably also explains why the manual states to use Unbuffered, but this is a recommendation, not a requirement.

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Well, after doing our recent project with over 20 v2 Z420s optimized I can say you don't need that UB memory.  You want a fast v2 processor for your v2 Z420, and you can run the specific DDR3 1866MHz 8GB buffered sticks in it I detailed  HERE .  You won't hurt anything by trying out your other memory you already own.  Just use one or the other.  Generally it is a bad idea to mix.


There is a minute speed benefit of UB over buffered.  You would never notice it.  There, however, is a significant data integrity benefit of buffered over UB.  There also is a significant speed benefit of 1866MHz memory over 1600 or 1333 so check that you are running an 1866 v2 processor and matching 1866 memory, all slots filled by identical memory.


My best buy on the memory I posted about was 10.00 USD/stick x 8 including shipping; all was HP server recycled memory.  Understand that there is a market force here.... excellent HP servers get upgraded before we'd even think of dumping our HP workstations.  Workstations that use server memory and processors benefit, thereby, as enterprises or their dumpster-divers recycle.

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