HP QuickSpecs Z8 G4 Manual page 17

QuickSpecs
System Technical Specifications
System Board
System Board Form Custom Form Factor, 16.34"x15.25" (415mm x 387.2mm )
Factor
Processor Socket
Dual FCLGA3647 (Socket P)
CPU Bus Speed UPI: Up to 10.4GT/second, depending on processor
Chipset Intel® C622 Chipset
Super I/O Controller
Nuvoton SIO15
Memory Expansion 24 slots (12 slots per CPU)
Slots
DDR4 R-DIMM (Registered), ECC: 8GB, 16GB, and 32GB
Memory Type
DDR4 LR-DIMM (Load Reduced), ECC: 64GB (128GB and 256GB added after initial release)
Supported
Memory Modes
NUMA (Non-Uniform Memory Architecture), Memory Node Interleave
Memory Speed 2133MT/s, 2400MT/s, and 2666MT/s
Supported
Memory Loading Order:
Load Order for Single and Dual Processor Configuration
Maximum Memory Supports up to 768GB using RDIMMs
Supports up to 3TB using LRDIMMs*
Memory Configuration Only ECC Registered DIMMs are supported.
(Supported)
Notes For systems installed with 32 bit operating systems, the max accessible system memory is 4GB.

RDIMM (Registered) and LR DIMM (Load Reduction) memory cannot be mixed. All memory
installed in the system must be either RDIMM or LR DIMM.

Do not install memory modules into memory slots if corresponding processor is not installed.

Dual processor configurations with memory modules installed for only one processor is not
supported.
c05527763 — DA - 15956 Worldwide — Version 3 — November 1, 2017
HP Z8 G4 Workstation
Page 17