HPE ProLiant DL345 Gen12 Memory

Genuine HPE DDR5 Smart Memory for the HPE ProLiant DL345 Gen12, new and refurbished, tested before shipping. This is a single-socket server with 24 DDR5 DIMM slots on one 5th Gen AMD EPYC 9005 processor — 12 channels, two DIMMs per channel — and the decision that matters most is not which kit but how many, because slot count sets the memory clock.

DL345 Gen12 Memory Specifications

• Type: HPE DDR5 Smart Memory Registered (RDIMM) EC8 kits, VR-on-DIMM power architecture and Advanced ECC; LRDIMM and persistent memory are not supported
• Slots: 24 in total — 12 channels per processor, 2 DIMMs per channel, all on the single socket
• Kits listed: 32GB dual-rank x8, 64GB, 96GB and 128GB dual-rank x4, all DDR5-6400 CAS-52, and a 256GB quad-rank x4 3DS kit at CAS-60
• Operating speed: every kit is rated DDR5-6400, and the kit operating-speed matrix lists 5200 MT/s at one DIMM per channel (1 to 12 DIMMs) and 4000 MT/s at two DIMMs per channel (16 to 24 DIMMs); the platform summary in the same document gives the 2DPC figure as 4400 MT/s
• Maximum memory: 3.0TB as 12 × 256GB at 5200 MT/s (1DPC), 6.0TB as 24 × 256GB at 4000 MT/s (2DPC)
• Population: the DIMM quantity must be 1, 2, 4, 6, 8, 10, 12, 16, 20 or 24; x4 and x8 modules cannot be mixed, nor can 3DS and non-3DS modules; DDR5-5600 and DDR5-4800 DIMMs are not supported with these processors
• Cooling note: HPE requires the performance fan kit when 128GB or 256GB DIMMs are installed, even with a processor of 240W or less

Slot count sets the clock, and the 32GB and 256GB kits do not mix with the rest. One to twelve DIMMs run at 5200 MT/s; sixteen or more drop the whole bank to 4000 MT/s at two DIMMs per channel. The 32GB kit is the only x8 module and the 256GB kit the only 3DS module, and HPE supports neither mixed with the x4, non-3DS 64GB, 96GB and 128GB kits — so decide the module before you decide the count, and stop at twelve for full speed.

How much memory can the DL345 Gen12 hold?

Twelve DIMMs is the sweet spot: one module on each of the 12 channels gives the full 5200 MT/s and, with 128GB or 256GB kits, 1.5TB or 3TB. The sixteenth DIMM moves the whole bank to two per channel and the 4000 MT/s clock — so 12 × 256GB reaches 3TB at full speed where 24 × 128GB reaches the same 3TB and slows every module.

Choosing the Right DL345 Gen12 Memory

• Count before you buy. Only 1, 2, 4, 6, 8, 10, 12, 16, 20 or 24 DIMMs are valid quantities; a top-up has to land on one of them.
• Do not mix the 32GB kit with anything else. It is the one x8 module in the range; the 64GB, 96GB, 128GB and 256GB kits are x4, and HPE does not support mixing the two organizations.
• The 256GB kit is 3DS and stands alone. 3DS and non-3DS modules cannot be mixed, so moving to 256GB modules means replacing every DIMM, not adding to them.
• Buy DDR5-6400 only. DDR5-4800 and DDR5-5600 DIMMs are explicitly not supported with these processors, even though they are the same DDR5 form factor.
• Plan for the fans. 128GB and 256GB modules require the performance fan kit regardless of processor wattage; the 32GB to 96GB kits do not.

Complete Your DL345 Gen12 Build

Large DIMMs change the fan requirement, so check DL345 Gen12 processors, where the heat sink and fan rules live, alongside this page. Also available: DL345 Gen12 drives, storage controllers, networking adapters and power supplies, or the full DL345 Gen12 parts listing. The adjacent generation is DL345 Gen11 memory, and all Gen12 kits are grouped under HPE Gen12 server memory. Background reading: maximum memory configurations for HPE ProLiant Gen12 servers, understanding memory rank, why memory speed matters and what CAS latency means, plus the HPE parts by server model index.

DL345 Gen12 Memory FAQ

How much RAM does the DL345 Gen12 support?
6TB, as 24 x 256GB DDR5 RDIMMs at two DIMMs per channel. At one DIMM per channel the documented maximum is 3TB, as 12 x 256GB, and that configuration keeps the higher 5200 MT/s clock.

What type of memory does the DL345 Gen12 use?
HPE DDR5 Smart Memory Registered DIMMs (RDIMM) rated DDR5-6400, in 32GB, 64GB, 96GB, 128GB and 256GB 3DS kits. LRDIMM and persistent memory are not supported, and neither are DDR5-5600 or DDR5-4800 DIMMs.

What is the maximum memory speed of the DL345 Gen12?
The kit operating-speed matrix lists 5200 MT/s with one DIMM per channel, which is any valid quantity from 1 to 12 DIMMs, and 4000 MT/s with two DIMMs per channel, which is 16, 20 or 24 DIMMs. The platform summary in the same QuickSpecs quotes the two-DIMM-per-channel figure as 4400 MT/s. The kits themselves are rated 6400 MT/s.

Can I mix 32GB and 64GB DIMMs in a DL345 Gen12?
No. The 32GB kit is a dual-rank x8 module and the 64GB kit is dual-rank x4, and HPE states that x4 and x8 memory cannot be mixed. The 64GB, 96GB and 128GB kits are all x4 and share that organization.

How many DIMMs should I install in a DL345 Gen12?
One of the supported quantities: 1, 2, 4, 6, 8, 10, 12, 16, 20 or 24. Twelve is the practical target, because it puts one DIMM on each of the 12 channels at full 5200 MT/s; 16 or more drops to 4000 MT/s.

Do 128GB or 256GB DIMMs need anything else in the DL345 Gen12?
Yes, the performance fan kit. HPE requires performance fans when 128GB or 256GB DIMMs are selected, even with a processor of 240W or less that would otherwise run on the standard fan kit. The 256GB module is also 3DS and cannot be mixed with the other capacities.

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