Technical data sheet · ThinkSystem V3 Neptune DWC · 1U tray, two 2-socket nodes

Lenovo ThinkSystem SD665 V3 Neptune DWCSpecifications, configurations & comparisons

The ThinkSystem SD665 V3 Neptune DWC is a 1U water-cooled tray carrying two independent two-socket AMD EPYC nodes, and it runs only in Lenovo’s 6U DW612S enclosure, up to six trays per enclosure, fed by that enclosure’s power supplies and water manifold. It is built for HPC clusters; this page quotes figures per node unless they are marked per tray or per enclosure.

Multi-Node (1U tray)2 socketsAMD EPYC 9005AMD EPYC 9004XClarity Controller 2

12nodes per 6U enclosure6 trays × 2 nodes in the DW612S

320cores per node2 × EPYC 9845, 160 cores each

3TBDDR5 per node24 × 128 GB · water at 32 °C or less

45°Cmaximum inlet waterASHRAE W45 · processors up to 400 W

2PCIe 5.0 x16 slots per nodelow profile; drives use the same bays

0fans in the nodewater cools CPUs, memory, drives, adapters

Configure an SD665 V3 →Get a UK quote

Every figure checked against the Lenovo ThinkSystem SD665 V3 Neptune DWC Server (August 18, 2026)

Image: Lenovo

Form factor: Multi-Node (1U tray) · 2 sockets
Processors: AMD EPYC 9005 · AMD EPYC 9004
Memory: 24 × DDR5 RDIMM · up to 3 TB
Drive bays: Up to 4 · 6 backplane options
Expansion: 2 × PCIe
Boot: M.2 Enablement Kit
Management: XClarity Controller 2

01 — Overview

The SD665 V3 at a glance

Our read of Lenovo’s documentation: where the SD665 V3 is strong, and the limits worth knowing before you spec one.

Strengths

Two independent two-socket nodes share each 1U tray, so a 6U DW612S enclosure holds twelve nodes and a 42U rack takes up to six enclosures.
Water reaches the processors, memory, drives, M.2 and adapters through parallel cold-plate loops, which lets the nodes run without fans and, within the W45 limits, accept inlet water as warm as 45 °C.
Each node has 24 DDR5 slots (12 channels per processor), PCIe 5.0 slots, and 2 × 25GbE plus 1GbE on board before any adapter is fitted.
SharedIO lets one NVIDIA adapter serve both nodes of a tray, cutting the number of adapters and switch ports, while Socket Direct wires one adapter to both processors of a node.
With the water-cooled power supplies, Lenovo says essentially all system heat can be captured in water, depending on water and room temperatures.

Watch-outs

Nothing about it is standalone: the tray needs the DW612S enclosure, a water manifold and a coolant distribution unit, and Lenovo says servicing trays single-handed requires an onsite material lift.
Single-processor configurations are not supported, and memory must be 8 or 12 identical DIMMs per processor.
Storage is small and internal: up to four E3.S or 7mm drives, or two 15mm drives, in the space that would otherwise hold PCIe slots, none hot-swap, with no hardware RAID and no SAS. A node with both slots fitted keeps only its single M.2 NVMe drive.
There are no GPUs, no OCP slot, no storage HBAs and no flash adapters, and Lenovo lists Linux only — Windows Server and VMware ESXi are absent.
The 128 GB DIMMs that reach 3 TB need inlet water at 32 °C or below, and power capping is not supported.

Processors38 SKUs

Cores / CPU16–160

DIMM slots24

Backplanes6

Max bays4

PSU options4 · to 7,200 W

02 — Processors

38 supported processors, mapped

Each node takes exactly two processors from a list of 38: 19 5th Gen EPYC 9005 models, four of them Zen 5c, and 19 4th Gen EPYC 9004 models, including three Genoa-X and two Bergamo parts. Core counts run from 16 to 160 per processor and TDP from 200 W to 400 W, and no single-socket P-suffix parts are offered.

Processor landscape — cores × TDP

38 SKUs · 2 families

AMD EPYC 9005 19AMD EPYC 9004 19Bubble size = L3 cache · hover a bubble for the full SKU

Processor explorer

filter · sort · compare

Sort

Processor	Cores / threads	Base	L3 cache	TDP	W / core	Memory
AMD EPYC 9845	160 / 320	2.1 GHz	320 MB	390 W	2.4	DDR5-6400
AMD EPYC 9825	144 / 288	2.2 GHz	384 MB	390 W	2.7	DDR5-6400
AMD EPYC 9745	128 / 256	2.4 GHz	256 MB	400 W	3.1	DDR5-6400
AMD EPYC 9754	128 / 256	2.25 GHz	256 MB	360 W	2.8	DDR5-4800
AMD EPYC 9734	112 / 224	2.2 GHz	256 MB	340 W	3.0	DDR5-4800
AMD EPYC 9655	96 / 192	2.6 GHz	384 MB	400 W	4.2	DDR5-6400
AMD EPYC 9645	96 / 192	2.3 GHz	256 MB	320 W	3.3	DDR5-6400
AMD EPYC 9684X	96 / 192	2.55 GHz	1150 MB	400 W	4.2	DDR5-4800
AMD EPYC 9654	96 / 192	2.4 GHz	384 MB	360 W	3.8	DDR5-4800
AMD EPYC 9634	84 / 168	2.25 GHz	384 MB	290 W	3.5	DDR5-4800
AMD EPYC 9565	72 / 144	3.15 GHz	384 MB	400 W	5.6	DDR5-6400
AMD EPYC 9575F	64 / 128	3.3 GHz	256 MB	400 W	6.3	DDR5-6400
AMD EPYC 9555	64 / 128	3.2 GHz	256 MB	360 W	5.6	DDR5-6400
AMD EPYC 9535	64 / 128	2.4 GHz	256 MB	300 W	4.7	DDR5-6400
AMD EPYC 9554	64 / 128	3.1 GHz	256 MB	360 W	5.6	DDR5-4800
AMD EPYC 9534	64 / 128	2.45 GHz	256 MB	280 W	4.4	DDR5-4800
AMD EPYC 9475F	48 / 96	3.65 GHz	256 MB	400 W	8.3	DDR5-6400
AMD EPYC 9455	48 / 96	3.15 GHz	256 MB	300 W	6.3	DDR5-6400
AMD EPYC 9474F	48 / 96	3.6 GHz	256 MB	360 W	7.5	DDR5-4800
AMD EPYC 9454	48 / 96	2.75 GHz	256 MB	290 W	6.0	DDR5-4800
AMD EPYC 9365	36 / 72	3.4 GHz	192 MB	300 W	8.3	DDR5-6400
AMD EPYC 9375F	32 / 64	3.8 GHz	256 MB	320 W	10.0	DDR5-6400
AMD EPYC 9355	32 / 64	3.55 GHz	256 MB	280 W	8.8	DDR5-6400
AMD EPYC 9335	32 / 64	3 GHz	128 MB	210 W	6.6	DDR5-6400
AMD EPYC 9374F	32 / 64	3.85 GHz	256 MB	320 W	10.0	DDR5-4800
AMD EPYC 9384X	32 / 64	3.1 GHz	768 MB	320 W	10.0	DDR5-4800
AMD EPYC 9354	32 / 64	3.25 GHz	256 MB	280 W	8.8	DDR5-4800
AMD EPYC 9334	32 / 64	2.7 GHz	128 MB	210 W	6.6	DDR5-4800
AMD EPYC 9275F	24 / 48	4.1 GHz	256 MB	320 W	13.3	DDR5-6400
AMD EPYC 9255	24 / 48	3.25 GHz	128 MB	200 W	8.3	DDR5-6400
AMD EPYC 9274F	24 / 48	4.05 GHz	256 MB	320 W	13.3	DDR5-4800
AMD EPYC 9224	24 / 48	2.5 GHz	64 MB	200 W	8.3	DDR5-4800
AMD EPYC 9254	24 / 48	2.9 GHz	128 MB	200 W	8.3	DDR5-4800
AMD EPYC 9175F	16 / 32	4.2 GHz	512 MB	320 W	20.0	DDR5-6400
AMD EPYC 9135	16 / 32	3.65 GHz	64 MB	200 W	12.5	DDR5-6400
AMD EPYC 9174F	16 / 32	4.1 GHz	256 MB	320 W	20.0	DDR5-4800
AMD EPYC 9184X	16 / 32	3.55 GHz	768 MB	320 W	20.0	DDR5-4800
AMD EPYC 9124	16 / 32	3 GHz	64 MB	200 W	12.5	DDR5-4800

Lenovo’s guide conflicts on this: one line of its key-features list reads “one 5th Gen processor” per node, while its specification table (two per node), processor tables (quantity 2) and configuration notes (single-processor configurations not supported) all say two. This page follows those three.
The 45 °C water rating (ASHRAE W45) covers processors up to 400 W TDP, which includes every processor on the list.
On 5th Gen processors the memory bus reaches 6400 MHz only with DIMMs from Lenovo’s 6400 MHz table and current firmware, falling back to 6000 MHz otherwise; on 4th Gen it is 4800 MHz.
Lenovo recommends the Genoa-X models, which carry as much as 1150 MB of L3 cache, for EDA and CFD, and describes the Zen 5c models as built for core density and power efficiency.
Of each processor’s 128 PCIe 5.0 lanes, Lenovo counts 64 as available to adapters and NVMe drives. In this node the NVMe drives, the M.2 drive and slot 2 hang off CPU 1, and slot 1 off CPU 2.

03 — Memory

24 DIMM slots, 12 per processor

Each processor has 12 DDR5 channels with one DIMM per channel, giving a node 24 slots. Lenovo supports only 8 or 12 DIMMs per processor, every DIMM in the node must be the same part number, and for best performance it recommends filling all 12 channels.

Capacity with every slot filled

by DIMM size

Rated memory speed

from the processor table

Processor family	Up to
AMD EPYC 9005	6400 MT/s
AMD EPYC 9004	4800 MT/s

The 3 TB per-node maximum comes from 24 × 128 GB DIMMs, and 128 GB DIMMs require inlet water at 32 °C or less (ASHRAE W32); the 45 °C W45 rating covers DIMMs up to 64 GB, and the guide gives no water limit for the 96 GB modules.
Lenovo’s specification table and memory rules name 3DS and 9x4 RDIMMs, and its key features put the 3 TB maximum on 128 GB 3DS RDIMMs, but the memory option tables contain no 3DS or 9x4 part — only x4, 10x4 and x8 RDIMMs from 16 GB to 128 GB; the 128 GB module for 4th Gen is a 5600 MHz RDIMM that runs at 4800 MHz.
DIMMs rated 6400 MHz are for 5th Gen processors only, and the modules in the 4th Gen table for 4th Gen only.
SDDC (Chipkill) needs x4 DIMMs, and memory mirroring and rank sparing are not supported. Lenovo notes that 1.1 V DDR5 draws roughly 20% less power than 1.2 V DDR4.

04 — Storage

6 backplane options, up to 4 bays

There are no front-accessible drive bays. Each node has up to two internal bays near its front, and each bay holds either a low-profile PCIe adapter or drives: two E3.S 1T, two 7mm 2.5-inch or one 15mm 2.5-inch. The drives cannot be reached from the front and are not hot-swap, and every layout below is per node.

Headline layouts

front panel view

Front panel

Both bays given to storage: four E3.S 1T PCIe 5.0 NVMe SSDs, up to 61.44 TB with 15.36 TB drives, and no PCIe slot. The drives are numbered 0 to 3 and connect to CPU 1.

SAS/SATANVMeSAS/SATA + NVMe

Controllers & boot

Onboard 6Gb SATA ports (2x) — Software RAID. Onboard; no hardware RAID - RAID provided by the operating system
Onboard PCIe x4 NVMe ports (2x) — Software RAID. Onboard; NVMe drives connect to CPU 1; no hardware RAID - RAID provided by the operating system
M.2 Enablement Kit (BPZF) - 1 x M.2 NVMe PCIe 4.0 x4, 2280/22110, water-cooled, NVMe only (no SATA M.2) — boot

Every node also takes one M.2 NVMe drive (PCIe 4.0 x4, 2280 or 22110) on an adapter mounted on the front processor’s cold plate; SATA M.2 drives are not supported. It is the only internal storage when both PCIe slots are used.
Drives connect to onboard SATA or NVMe ports with no hardware RAID; RAID comes from the operating system. SAS drives, storage HBAs and flash storage adapters are not supported.
Field upgrades use one NVMe and one SATA storage option kit, each containing the cage and cables.
Lenovo’s specification table describes the 7mm bays as taking PCIe 5.0 NVMe drives, but every 7mm NVMe drive in its option tables is PCIe 4.0.
Drive Encryption Enablement (CES1) makes the factory configurator require self-encrypting drives and XCC2 Platinum; it does not turn encryption on at the factory.

Every documented backplane

6 with drive bays

2.5-inch3.5-inchEDSFF (E1.S / E3.S)

05 — I/O & networking

PCIe and networking

The SD665 V3 has no GPU support. For water-cooled NVIDIA H100 GPUs Lenovo points to the separate SD665-N V3, which pairs the same node with an NVIDIA HGX H100 4-GPU board and has its own product guide.

I/O topology

128 lanes per CPU

Each node pairs two processors, each with 128 PCIe 5.0 lanes (64 usable for PCIe and NVMe devices) and 12 memory channels. External I/O is three onboard network ports plus up to two low-profile PCIe 5.0 x16 slots on single-slot risers, and there is no OCP slot.

Network adapters Lenovo lists

7 options

Adapter	Ports	Form
Onboard Mellanox ConnectX-6 Lx 2 x 25GbE SFP28	2 × 25GbE	embedded
Onboard Intel I210 1 x 1GbE RJ45	1 × 1GbE	embedded
NVIDIA ConnectX-7 NDR OSFP400 1-port PCIe Gen5 x16 InfiniBand Adapter DWC (BKSN)	1 × NDR 400Gb InfiniBand	PCIe
NVIDIA ConnectX-7 NDR OSFP400 1-port PCIe Gen5 x16 InfiniBand Adapter (SharedIO) DWC (BKSP)	1 × NDR 400Gb InfiniBand	PCIe
NVIDIA ConnectX-7 NDR200/HDR QSFP112 2-port PCIe Gen5 x16 InfiniBand Adapter (SharedIO) DWC (BKSL)	2 × NDR200/HDR 200Gb InfiniBand	PCIe
Mellanox ConnectX-6 HDR/200GbE QSFP56 1-Port PCIe 4 VPI Adapter (SharedIO) DWC (BKSK)	1 × HDR/200GbE	PCIe
Cornelis CN5000 Omni-Path 1-Port QSFP112 HFI SuperNIC DWC (Generic FW) (CB7C)	1 × Omni-Path	PCIe

Adapters listed: ConnectX-7 NDR OSFP400 InfiniBand (standalone or SharedIO versions), ConnectX-7 NDR200/HDR 2-port, ConnectX-6 HDR/200GbE and the Cornelis CN5000 Omni-Path SuperNIC, which needs the CGF4 riser in slot 2. All are DWC (water-cooled) versions.
SharedIO (NVIDIA Multi-Host): an adapter in slot 2 of node 2 is cabled to node 1 so both nodes share one network connection, one adapter per tray, and each node’s slot 1 can then carry two 7mm drives or one 15mm drive. The ConnectX-6 cannot run SharedIO when water-cooled power supplies are configured.
Socket Direct: an adapter in slot 2 is cabled to slot 1’s connector so it reaches both processors; slot 1 stays empty, and each link runs at PCIe Gen4, which Lenovo says matches Gen5 throughput in total.
Local console is a breakout cable that plugs into the node front and provides VGA, serial and USB 3.1 Gen 1 connectors; the node also has a port for the External Diagnostics Handset.
The DW612S midplane carries power and control signals only, not I/O, so all networking runs to top-of-rack switches.

06 — Power & cooling

4 power supplies, 2,400–7,200 W

Power is an enclosure resource: the DW612S takes six or nine air-cooled supplies, or two or three water-cooled units that each contain three supplies, in a single power domain for all installed nodes. Supplies must be the same part number; the 230 V units accept only high-range 200–240 V AC input, and Lenovo’s power-supply section lists N+1 (5+1 or 8+1) or non-redundant policies depending on configuration and node population.

AC277 VAC / HVDC

Air-cooled options are a 2400 W Platinum and a 2600 W Titanium unit (both C19), plus a 2600 W Titanium HVAC unit on an RF-203-HP connector offered only in the USA. The water-cooled 7200 W Titanium unit takes three C19 cords.
Output depends on input voltage: on 200–208 V the 2600 W unit delivers 2400 W and the 7200 W unit 6900 W, while the 2400 W unit is unchanged.
Maximum current is 13.2 A (200–208 V) or 13 A (220–240 V) per 2600 W supply, and 12.7 A or 12 A per input on the 7200 W unit.
The enclosure specification table also mentions N+N redundancy and oversubscription, which the power-supply section does not list.
Water-cooled supplies need an additional manifold. With them, Lenovo says nearly all of the system’s heat can be recovered into water, the exact share depending on water and room temperatures, and it gives about 95% as the typical figure at 45 °C water and 30 °C room temperature. These are system figures, not per node.
Water limits: up to 3.5 bar per rack, typically 12 L/min per enclosure (2.0 L/min per tray) at W45, and a minimum of 9 L/min per enclosure (1.5 L/min per tray) at W32. Fill water must be clean (under 100 CFU/ml) and filtered through a 50-micron in-line filter.

07 — Management, security & OS

Run it, secure it, choose the OS

Management

XClarity Controller 2 (XCC2) on an ASPEED AST2600 in each node
System Management Module 2 (SMM2) in the DW612S: enclosure power, cooling, inventory and node virtual reseat
SMM2 daisy chain: one Ethernet link for up to 7 enclosures and 84 nodes (6 enclosures with spanning tree)
NC-SI shared management on the onboard 1GbE port and 25GbE port 1
XCC2 Platinum upgrade: remote console, virtual media, System Guard, Enterprise Strict Security (CNSA 1.0), Neighbor Group
TI INA226 power meter: processor DC power sampled at 100 Hz with better than 97% accuracy
Lenovo HPC & AI Software Stack: Confluent, Slurm, Slinky, Energy Aware Runtime, Open OnDemand
XClarity Provisioning Manager, XClarity One, XClarity Essentials, XClarity Energy Manager (no power capping or policy management)
Drip sensors at the manifold quick-connect couplers report leaks through the SMM

Security

Platform Firmware Resiliency hardware Root of Trust (NIST SP 800-193)
TPM 2.0 · Nationz TPM 2.0 for China (CTO only)
AMD Platform Secure Boot, SEV, SEV-ES, SEV-SNP and TSME
UEFI Secure Boot (cannot be disabled once enabled)
System Guard (XCC2 Platinum)
NIST SP 800-147B compliant · FIPS 140-3 (in progress) and CNSA Suite 1.0 for XCC

Operating systems

Red Hat Enterprise Linux 8.10, 9 and 10 (from 8.6 with 4th Gen EPYC)
SUSE Linux Enterprise Server 15 SP6, SP7 and 16 (from SP4 with 4th Gen)
Ubuntu 22.04, 24.04 and 26.04 LTS (20.04 with 4th Gen)
Also certified or tested: Rocky Linux, AlmaLinux
No Windows Server or VMware ESXi listed

08 — Compare

How the SD665 V3 compares with its family

The DW612S also accepts Lenovo’s other water-cooled V3 and V2 trays, among them the GPU-based SD665-N V3. The family matrix compares the SD665 V3 with the air-cooled SD535 V3 node, the SC750 V4 Neptune tray (Xeon 6, N1380 enclosure) and the SR645 V3 and SR665 V3 two-socket EPYC rack servers.

This modelSiblings and successorEach value from that model’s own verified spec file · bars scale per column

SD535 V3 data sheet SC750 V4 data sheet SR645 V3 data sheet SR665 V3 data sheet Dell PowerEdge C6615 data sheet Dell PowerEdge R6625 data sheet

09 — Use cases

Four builds that suit the SD665 V3

Four example nodes built from the options our configurator offers for the SD665 V3. Each build is one node — half a tray — and the DW612S enclosure, its power supplies and the water manifold are quoted separately; before quoting we check water temperature, slot and drive combinations against Lenovo’s rules.

HPC cluster

NDR 400 MPI compute node

Two 96-core EPYC 9655 processors give 192 cores per node at 400 W each, the highest TDP the 45 °C water rating covers. Twenty-four 64 GB DIMMs fill every channel within the same W45 limit, one NDR 400 Gb InfiniBand card handles the fabric, and two E3.S drives provide local scratch.

2 × AMD EPYC 9655 — 96 cores @ 2.6 GHz, 400 W each
24 × 64 GB TruDDR5 6400 MHz — 1.5 TB, 12 per processor
2 × 7.68 TB E3.S 1T NVMe in one internal bay
NVIDIA ConnectX-7 NDR OSFP400 1-port InfiniBand (DWC) in the other bay
Red Hat Enterprise Linux 9

With one bay given to drives the node has a single PCIe slot. The drives use onboard ports without hardware RAID, and the tray, enclosure power and water manifold are ordered separately. Lenovo’s W45 rating names NVIDIA cards up to 200 Gb/s and gives no water limit for this 400 Gb card, so we confirm the inlet water temperature with Lenovo before quoting.

Open this build in the configurator →

Memory-bound simulation

3 TB high-frequency node

For codes limited by memory capacity, twenty-four 128 GB DIMMs give the node’s 3 TB maximum, paired with two EPYC 9575F processors that boost to 5 GHz. The trade-off is water temperature: Lenovo limits 128 GB DIMMs to inlet water of 32 °C or less.

2 × AMD EPYC 9575F — 64 cores @ 3.3 GHz, 400 W each
24 × 128 GB TruDDR5 6400 MHz — 3 TB
2 × 3.84 TB E3.S 1T NVMe
NVIDIA ConnectX-7 NDR200/HDR 2-port InfiniBand (DWC)
Ubuntu 22.04 LTS

ASHRAE W32 applies: inlet water must stay at or below 32 °C, which can call for more facility cooling than the 45 °C W45 rating used elsewhere. The same NDR200 card can instead be shared by both nodes in the tray through SharedIO.

Open this build in the configurator →

Engineering CFD & EDA

Genoa-X large-cache node

Two EPYC 9684X processors bring 96 cores and 1150 MB of L3 cache each, the Genoa-X parts Lenovo suggests for EDA and CFD. Their 4th Gen memory controllers top out at 4800 MHz, so matching 4800 MHz modules are specified, and twenty-four 64 GB DIMMs keep the node inside the 45 °C water rating.

2 × AMD EPYC 9684X — 96 cores @ 2.55 GHz, 400 W each
24 × 64 GB TruDDR5 4800 MHz — 1.5 TB
2 × 3.84 TB E3.S 1T NVMe
Mellanox ConnectX-6 HDR/200GbE 1-port (DWC)
Red Hat Enterprise Linux 9

Lenovo lists the ConnectX-6 for this node only in its water-cooled DWC version, and that card cannot run SharedIO in an enclosure with water-cooled power supplies.

Open this build in the configurator →

Throughput computing

320-core Zen 5c node

Two 160-core EPYC 9845 processors give 320 cores per node, so a full DW612S holds 3,840 cores in 6U. Zen 5c is the architecture Lenovo lists for core density and power efficiency, and at 390 W these parts sit within the W45 water rating.

2 × AMD EPYC 9845 — 160 cores @ 2.1 GHz, 390 W each
24 × 64 GB TruDDR5 6400 MHz — 1.5 TB
2 × 7.68 TB E3.S 1T NVMe
NVIDIA ConnectX-7 NDR200/HDR 2-port InfiniBand (DWC)
Ubuntu 24.04 LTS

If the onboard 2 × 25GbE ports cover the network, the adapter bay can take two more E3.S drives instead, for four per node.

Open this build in the configurator →

10 — Full specifications

Lenovo ThinkSystem SD665 V3 Neptune DWC specifications

Tray, node & enclosure

Form factor	Two independent 2-socket nodes on a 1U water-cooled tray
Machine types	Tray 7D9P (3-year) · DW612S enclosure 7D1L · water manifold 5469
Tray dimensions (W × H × D)	438 × 41 × 714 mm · 769 mm including the rear water connections
Tray weight	23.6 kg maximum
Enclosure	ThinkSystem DW612S, 6U · 447 × 264 × 933 mm · 6 trays, 12 nodes
Enclosure weight	24.3 kg empty · 182.9 kg (9 air-cooled supplies) or 188.7 kg (3 water-cooled supplies) with 6 trays, without manifold
Per rack	Up to 6 enclosures per 42U rack, 7 per 48U rack
Models	Configure-to-order only (7D9PCTOLWW)

Processor

Sockets	Two per node (single-processor builds not supported)
Families	5th Gen EPYC 9005 (Zen 5, Zen 5c) · 4th Gen EPYC 9004 (Genoa, Genoa-X, Bergamo)
Cores per processor	16–160 (5th Gen) · 16–128 (4th Gen)
TDP	200–400 W
PCIe lanes	128 × PCIe 5.0 per processor, 64 available for PCIe and NVMe devices

Memory

Slots	24 DDR5 per node · 12 channels × 1 DIMM per processor
Population	8 or 12 identical DIMMs per processor
DIMM sizes listed	16, 32, 64, 96 and 128 GB RDIMM
Speed	Up to 6400 MHz (5th Gen) · 4800 MHz (4th Gen)
Maximum	3 TB per node (24 × 128 GB; water at 32 °C or less)
Protection	ECC, SDDC (x4), Bounded Fault, patrol/demand scrubbing, Post Package Repair · no mirroring or rank sparing

Storage

Internal bays	2 per node, each holding 1 PCIe adapter, 2 × E3.S 1T, 2 × 7mm or 1 × 15mm drive
Maximum	4 × E3.S, 4 × 7mm or 2 × 15mm (no PCIe slots) · 61.44 TB
Drive types	E3.S PCIe 5.0 NVMe · 7mm SATA or NVMe (listed 7mm NVMe drives are PCIe 4.0) · 15mm PCIe 5.0 or 4.0 NVMe · no SAS
Boot	1 × M.2 NVMe, PCIe 4.0 x4, on the CPU 1 cold plate
RAID	None in hardware · operating-system RAID

Networking & I/O

Onboard	2 × 25GbE SFP28 (ConnectX-6 Lx) · 1 × 1GbE RJ45 (Intel I210)
PCIe	1 or 2 × PCIe 5.0 x16 low-profile per node
Adapters	NDR 400 and NDR200 InfiniBand, HDR/200GbE, CN5000 Omni-Path (DWC versions)
Adapter sharing	SharedIO (1 per tray) · Socket Direct
GPU and OCP	Neither supported

Power & cooling

Cooling	Direct water cooling, no node fans
Water	2–45 °C inlet (ASHRAE W45) · 32 °C or less for 128 GB DIMMs · 3.5 bar maximum per rack
Flow	Typical 12 L/min per enclosure (2.0 per tray) at W45 · minimum 9 L/min per enclosure (1.5 per tray) at W32
Enclosure supplies	6 or 9 air-cooled (2400 or 2600 W) or 2 or 3 water-cooled (7200 W), hot-swap
Input	200–240 V AC · 180–300 V DC in China · 277 V AC HVAC unit in the USA

Ports & management

Node front	External diagnostics port · console breakout (VGA, serial, USB 3.1 Gen 1) · operator panel
Enclosure	SMM2 with two 1GbE RJ45 ports
Video	16 MB in XCC · 1920 × 1200 at 60 Hz

Environment & warranty

Air temperature	10–35 °C operating (ASHRAE A2)
Humidity	8–80% operating, dew point up to 21 °C
Warranty	3 years for tray, enclosure and manifold · CRU and onsite, 9 × 5 next business day

11 — FAQ

SD665 V3 questions, answered from the documentation

Can the SD665 V3 be used without the DW612S enclosure?

No. The SD665 V3 is a 1U tray of two nodes that installs only in the 6U ThinkSystem DW612S Neptune DWC enclosure, which supplies power, the System Management Module and the water connections. The enclosure in turn needs a water manifold connected to a coolant distribution unit.

How many processors and cores does each SD665 V3 node have?

Exactly two AMD EPYC processors per node; single-processor builds are not supported. The largest is the 160-core EPYC 9845, giving 320 cores per node and 640 per tray.

What is the maximum memory of the SD665 V3?

3 TB per node with 24 × 128 GB DIMMs, 12 per processor. Those DIMMs need inlet water at 32 °C or below; with 64 GB DIMMs (1.5 TB per node) the water can be as warm as 45 °C.

What storage does an SD665 V3 node have?

Up to four internal E3.S or 7mm SSDs, or two 15mm NVMe SSDs, fitted in bays that otherwise hold PCIe adapters, plus one M.2 NVMe boot drive. None of it is hot-swap or front-accessible, there is no hardware RAID, and SAS is not supported.

Does the SD665 V3 support GPUs?

No. Lenovo’s water-cooled GPU option is the SD665-N V3, which combines the same node with an NVIDIA HGX H100 4-GPU board and has its own product guide.

What networking does the SD665 V3 have?

Each node has two 25GbE SFP28 ports and one 1GbE RJ45 port on board, plus one or two PCIe 5.0 x16 slots for NDR or NDR200 InfiniBand, HDR/200GbE or Omni-Path adapters. SharedIO lets the two nodes in a tray share one adapter, and there is no OCP slot.

What water temperature does the SD665 V3 need?

Up to 45 °C inlet water (ASHRAE W45) for processors up to 400 W, DIMMs up to 64 GB and NVIDIA HDR/NDR cards up to 200 Gb/s; 128 GB DIMMs lower the limit to 32 °C (W32). Pressure must not exceed 3.5 bar per rack, and typical flow is 12 L/min per enclosure. The guide gives no water limit for 96 GB DIMMs, the 400 Gb NDR card or the Omni-Path adapter.

How are SD665 V3 nodes powered?

Through the DW612S enclosure: six or nine air-cooled supplies (2400 W Platinum or 2600 W Titanium) or two or three 7200 W water-cooled supplies, one part number throughout. The 230 V units need 200–240 V AC, and a USA-only 2600 W HVAC unit takes 277 V AC. The power-supply section lists N+1 or non-redundant policies depending on configuration and node population; the enclosure table also mentions N+N.

Which operating systems run on the SD665 V3?

Lenovo lists Red Hat Enterprise Linux, SUSE Linux Enterprise Server and Ubuntu, and names Rocky Linux and AlmaLinux as certified or tested. Windows Server and VMware ESXi are not listed for this node.

Is the SD665 V3 end of life?

Its product guide, dated August 18, 2026, includes 5th Gen EPYC processors and RHEL 10.2 support and gives no end-of-service date for the model. Individual trays are covered by their warranty or Lenovo service contract, and our end-of-life checker tracks any date Lenovo announces.

Sources & verification

Where these figures come from

Lenovo ThinkSystem SD665 V3 Neptune DWC Server (August 18, 2026) — Key features, tray and DW612S specifications (Tables 1–2), CTO and manifold models (Tables 3–7), processor Tables 9–12, memory Tables 14–15 and rules, internal storage and M.2 (Tables 16–26), risers (Table 28), network adapters, SharedIO and Socket Direct (Table 29), cooling, power supplies (Tables 30–32), systems management and SMM2, security, OS support, physical and electrical specifications, operating environment and warranty.

Specifications are extracted from Lenovo’s published documents and independently re-checked line by line. Configurations are quote-based; availability and exact options are confirmed at quotation. Last reviewed 2026-09-11.

Get a quote for the Lenovo ThinkSystem SD665 V3 Neptune DWC

Tell us the workload and we’ll spec and price it — or build it in the configurator first.

Business enquiries only — please use your company email. Gmail, Hotmail and other personal addresses are not accepted.

Delivery country (optional)

We only ship hardware to the countries in the dropdown. Software and maintenance services are global.

Enquiring about: Lenovo ThinkSystem SD665 V3 Neptune DWC

Full Name *

Email *

Company

Quantity Required

Additional Notes

Response within 4 business hours · No obligation

Quote for

Lenovo ThinkSystem SD665 V3 Neptune DWC

0800 987 4111

The SD665 V3 at a glance

Strengths

Watch-outs

38 supported processors, mapped

Processor landscape — cores × TDP

Processor explorer

24 DIMM slots, 12 per processor

Capacity with every slot filled

Rated memory speed

6 backplane options, up to 4 bays

Headline layouts

Controllers & boot

Every documented backplane

PCIe and networking

I/O topology

Network adapters Lenovo lists

4 power supplies, 2,400–7,200 W

Run it, secure it, choose the OS

Management

Security

Operating systems

How the SD665 V3 compares with its family

Four builds that suit the SD665 V3

NDR 400 MPI compute node

3 TB high-frequency node

Genoa-X large-cache node

320-core Zen 5c node

Lenovo ThinkSystem SD665 V3 Neptune DWC specifications

Tray, node & enclosure

Processor

Memory

Storage

Networking & I/O

Power & cooling

Ports & management

Environment & warranty

SD665 V3 questions, answered from the documentation

Where these figures come from

Buy & configure

Liquid cooling & HPC

Family & dense compute

Plan & support

Get a quote for the Lenovo ThinkSystem SD665 V3 Neptune DWC

Talk to a UK specialist