Lenovo ThinkSystem SR645

Lenovo's 2-socket 1U rack server (machine types 7D2X/7D2Y) for AMD EPYC 7002 "Rome" and 7003 "Milan"/"Milan-X" processors up to 64 cores and 280 W, with 32 DDR4-3200 DIMM slots (up to 8 TB), up to 12 x 2.5-inch or 4 x 3.5-inch hot-swap drives (up to 12 NVMe without switches), up to three PCIe 4.0 slots and an OCP 3.0 slot. Aimed at HPC, databases, virtualization and VDI where rack density matters.

Memory

Slots: 32 DIMM (16 per processor; 8 channels per CPU, 2 DIMMs per channel)
Types: Lenovo TruDDR4 RDIMM (16, 32, 64 GB), 3DS RDIMM (128, 256 GB) and Performance+ RDIMM (32, 64 GB); no mixing of RDIMM with 3DS RDIMM, or Performance+ with standard DIMMs
Speed: RDIMM 3200 MHz at 1 DPC / 2933 MHz at 2 DPC; 3DS RDIMM 2933 / 2666 MHz; Performance+ RDIMM 3200 MHz at both 1 and 2 DPC
Max: 8 TB (32 x 256 GB 3DS RDIMM); 2 TB with one processor
Population: Best performance with 8 or 16 DIMMs per processor (all channels used); at most two DIMM capacities per processor
Persistent memory: Not supported
Protection: ECC, SDDC (x4 DIMMs), Patrol/Demand Scrubbing, DRAM Address Command Parity with Replay, DRAM Uncorrected ECC Error Retry, Post Package Repair; no mirroring or rank sparing

Storage

Front 2.5": 4, 8 or 10 x 2.5" SAS/SATA; 6 SAS/SATA + 4 AnyBay; 6 SAS/SATA + 4 NVMe; 6 SAS/SATA + 2 AnyBay + 2 NVMe; 10 x AnyBay; 10 x NVMe; 8 AnyBay + 2 NVMe
Front 3.5": 4 x 3.5" SAS/SATA or 4 x 3.5" AnyBay
Rear: 2 x 2.5" hot-swap SAS/SATA or NVMe, or 2 x 7mm SATA or NVMe (with integrated Marvell RAID controller)
Maximum: 12 x 2.5" (10 front + 2 rear), all NVMe with direct 1:1 connections; or 4 x 3.5" + 2 x 2.5" rear
Capacity: Up to 737.28 TB (12 x 61.44 TB NVMe SSD) or 88 TB (4 x 22 TB 3.5" HDD)
Controllers: Onboard SATA (up to 12 drives, JBOD only), onboard NVMe (no RAID), 4-port PCIe 4.0 NVMe retimer, RAID 530/540/930/940/5350/9350 8i and 16i (up to 8 GB flash cache; 940 Tri-Mode for U.3 NVMe), 430/440/4350 8i and 16i HBAs
Internal RAID bay: With 2.5" front bays, a cabled internal RAID 940-16i, 9350-8i/16i, 5350-8i or HBA 440-16i can sit between drives and fans without using a PCIe slot (needs two CPUs)
M.2 boot: Internal M.2 module for 1 or 2 drives: SATA RAID (Marvell 88SE9230), NVMe RAID (Marvell 88NR2241) or SATA/NVMe non-RAID; 2242 to 22110
Optical: None internal; external USB DVD-RW option

Graphics

Onboard: Matrox G200 in the XClarity Controller, 16 MB, max 1920x1200 at 60 Hz
GPU options: NVIDIA A2 16GB, T4 16GB, Quadro P620 2GB (up to 3, slots 1-3); Quadro P2200 5GB (1, slot 2)
Rules: All GPUs identical; no rear drive bays; performance fans required; 2 GPUs max (slots 1 and 3) with 225 W or 280 W CPUs

Expansion

Slot 1: PCIe 4.0 x16, low profile (riser 1, CPU 1)
Slot 2: PCIe 4.0 x16, low profile or full-height half-length (riser 1, CPU 1)
Slot 3: PCIe 4.0 x16, low profile (riser 2, needs CPU 2)
OCP: Dedicated OCP 3.0 SFF slot, PCIe 4.0 x16
Slot layouts: 3 x LP; 1 x LP + 1 x FHHL; 1 x LP + 2 x 2.5" rear drives; 2 x LP + 2 x 7mm rear drives
PCIe 3.0 option: Lower-cost PCIe 3.0 x16/x16 riser 1 for slots 1-2
Internal: Cabled PCIe 4.0 x8 connector for an internal RAID adapter/HBA (2.5" chassis only)
Serial: Optional DB-9 COM port kit installs in slot 3

Networking

OCP 3.0: Optional 2- or 4-port adapters: 1 GbE (Broadcom 5719, Intel I350), 10GBASE-T (Broadcom 57416/57454, Intel X710-T2L/T4L, Marvell QL41132), 10/25 GbE SFP28 (Broadcom 57414/57454/57504, Intel E810-DA2/DA4, Marvell QL41232, Mellanox ConnectX-4 Lx / ConnectX-6 Lx); one port can be shared with the XCC
PCIe: 1/10/25 GbE, 100 GbE (Broadcom 57508, ConnectX-6 Dx), InfiniBand HDR100/HDR and NDR200/NDR 400 Gb (ConnectX-6, ConnectX-7)
Fibre Channel: Emulex LPe35000/35002 32Gb, QLogic QLE2770/2772 32Gb, Emulex and QLogic 16Gb HBAs
Management: 1 x RJ-45 10/100/1000 Mb XClarity Controller port

Power

PSU options: 500 W, 750 W, 1100 W Platinum (115/230 V), 1800 W Platinum (230 V), 750 W, 1100 W, 1800 W Titanium (230 V), 1100 W -48 V DC
Redundancy: 1 or 2 hot-swap PSUs; both must be identical (the two 500 W Platinum versions may be mixed)
Connector: C14 inlets on AC units; Weidmuller TOP 4GS/3 7.6 terminal on the -48 V DC unit
Input current: 100-127 V: 500 W 5.7 A, 750 W Platinum 8.4 A, 1100 W 12 A; 200-240 V: 500 W 2.7 A, 750 W 4.1 A, 1100 W 6 A, 1800 W 10 A
Cooling: 6 (one CPU) or 8 (two CPUs) hot-swap 40 mm dual-rotor fans; standard (21K RPM) or performance (28K RPM); one fan in each PSU
Heat output: 264 W (900 BTU/hr) minimum to 857 W (2924 BTU/hr) maximum configuration

Ports

Front: 1 x USB 3.1 Gen 1, 1 x USB 2.0 (XClarity Controller management), external diagnostics handset port, optional VGA
Rear: 3 x USB 3.1 Gen 1, 1 x VGA, 1 x RJ-45 XCC management, NMI button; optional DB-9 serial (slot 3)
Internal: 1 x USB 3.2 Gen 1 (OS or licence key)

Physical

Form factor: 1U rack
Dimensions: 440 mm W x 43 mm H x 773 mm D (17.3 x 1.7 x 30.4 in); 482 mm across the rack flanges
Weight: Maximum 20.2 kg (44.6 lb)
Machine types: 7D2X (3-year warranty), 7D2Y (1-year warranty)
Environment: ASHRAE A2 (10-35 C) for most configurations; A3/A4 only with CPUs up to 170 W and no NVMe, GPUs, rear drives or 128 GB+ DIMMs
Acoustics: Idle 43 dBA typical, operating 49 dBA typical (59 dBA GPU- or storage-rich)

Management

BMC: Lenovo XClarity Controller (Pilot4 XE401, dual-core ARM Cortex A9); Standard, Advanced (remote KVM up to 1600x1200) or Enterprise (virtual media, boot capture)
Interfaces: IPMI 2.0 (IPMI-over-LAN off by default), SNMPv3, CIM-XML, REST, Redfish, HTML5 web UI; dedicated 1 GbE RJ-45 port, or NC-SI shared on an OCP port
Software: XClarity Provisioning Manager (F1), Administrator, Integrators, Essentials, Energy Manager, Capacity Planner; XClarity Mobile via the front USB management port
Security: TPM 2.0 (TPM 1.2 also with EPYC 7002; Nationz TPM 2.0 in China), AMD Platform Secure Boot, UEFI Secure Boot, Platform Firmware Resiliency (NIST SP 800-193), NIST SP 800-147B, intrusion switch, optional lockable bezel
Local: Front operator panel; optional pull-out Integrated Diagnostics Panel (LCD) on 8 x 2.5" fronts (CTO only); External Diagnostics Handset port; light path LEDs for CPUs, DIMMs, drives, fans and PSUs
Announced: Product guide first published 2020-05-05
Withdrawn: Withdrawn from marketing (Lenovo Press update of 2026-03-19); suggested replacement SR645 V3

Operating systems

Windows: Windows Server 2016, 2019, 2022; 2025 with EPYC 7003 only
Linux: RHEL 8.3-8.10, 9.0-9.8, 10.0-10.2 (EPYC 7002 also RHEL 7.6-7.9, 8.1, 8.2); SLES 12 SP5, 15 SP2-SP7 (SP1 on EPYC 7002), 16; Ubuntu 22.04, 24.04, 26.04 LTS
VMware: ESXi 6.7 U3, 7.0 (EPYC 7002) / 7.0 U1-U3, 8.0-8.0 U3, 9.0, 9.1; factory ESXi preload available (not with NVIDIA GPUs)

Processors

AMD EPYC 7203
AMD EPYC 7203P
AMD EPYC 72F3
AMD EPYC 7303
AMD EPYC 7303P
AMD EPYC 7313
AMD EPYC 7313P
AMD EPYC 7343
AMD EPYC 73F3
AMD EPYC 7413
AMD EPYC 7443
AMD EPYC 7443P
AMD EPYC 7453
AMD EPYC 74F3
AMD EPYC 7513
AMD EPYC 7543
AMD EPYC 7543P
AMD EPYC 75F3
AMD EPYC 7643
AMD EPYC 7643P
AMD EPYC 7663
AMD EPYC 7663P
AMD EPYC 7713
AMD EPYC 7713P
AMD EPYC 7763
AMD EPYC 7373X
AMD EPYC 7473X
AMD EPYC 7573X
AMD EPYC 7773X
AMD EPYC 7232P
AMD EPYC 7252
AMD EPYC 7262
AMD EPYC 7F32
AMD EPYC 7272
AMD EPYC 7282
AMD EPYC 7302
AMD EPYC 7302P
AMD EPYC 7F52
AMD EPYC 7352
AMD EPYC 7402
AMD EPYC 7402P
AMD EPYC 7F72
AMD EPYC 7452
AMD EPYC 7502
AMD EPYC 7502P
AMD EPYC 7532
AMD EPYC 7542
AMD EPYC 7552
AMD EPYC 7642
AMD EPYC 7662
AMD EPYC 7702
AMD EPYC 7702P
AMD EPYC 7742
AMD EPYC 7H12