Z840 use all 2Rx4 memory?

[mwx]

Will a z840 utilize modules like a 16GB 2Rx4 PC4-2133P-RB1-11 Registered ECC Memory DDR4. So far I have seen only 1Rx4 mentioned but have seen the 2R4 listed as compatible at some sites. If there were 1R4 chips originally I surmise I must remove if I use any 2Rx4?

[DGroves · Accepted solution]

the z840 has multiple ram banks (4 if dual cpu) 2 if single cpu, each bank can use different rank memory, however you can not mix different rank dimms in a bank dual rank ram is preferred as it's slightly faster

in lower capacity dimm sizes single and dual rank modules are available ,.....in higher capacity only dual rank and the largest sizes are quad rank

please refer to the hp z840 documentation on ram which is posted on the hp site under the z840 section

Supported memory modules

Types of memory supported on an HP Z840 are:

• 4 GB, 8 GB, and 16 GB PC4-2133R 2133 MHz DDR4 Registered DIMMs

• 32 GB, 64 GB, and 128 GB PC4-2133L 2133 MHz DDR4 LR DIMMs

– 64 GB LR DIMMs are expected to be available early 2015

– 128 GB LR DIMMs are expected to be available late 2015

• Single and dual rank 4 GB and 8 GB based DIMMs are supported

• Quad and octal rank 4 GB and 8 GB based LR DIMMs are supported

Types of memory NOT supported on an HP Z840 are:

• Unbuffered DIMMs

• Non-ECC DIMMs

• DDR, DDR2, or DDR3 DIMMs

See Memory Technology White Paper for more memory module technical information

https://zworkstations.com/site/assets/files/1044/hp-z840-technical-white-paper.pdf

Maximum capacity

• Single processor: 256 GB at launch

– 512 GB when 64 GB LR DIMMs are available

– 1 TB when 128 GB LR DIMMs are available

• Dual processors: 512 GB at launch

– 1 TB when 64 GB LR DIMMs are available

– 2 TB when 128 GB LR DIMMs are available

Total of 16 memory sockets

• 8 memory sockets available per CPU

• 4 channels per processor and 2 sockets per channel

Speed

• 2133 MHz, 1866 MHz, and 1600 MHz memory speeds are supported in this platform.

• Memory will operate at the speed of the slowest rated installed processor or DIMM.

Registered and LR DIMMs cannot be mixed in a system

Dynamic power saving is enabled

NUMA and Non-NUMA modes are supported and user configurable