ThinkSystem SR645
High core count 1U for virtualization density, HPC and cloud-native workloads.
The ThinkSystem SR645 is a previous-generation model, still supported and widely deployed. High core count 1U for virtualization density, HPC and cloud-native workloads.
Platform facts
| Vendor | Lenovo |
|---|---|
| Generation | Gen 1 (AMD) |
| Family | ThinkSystem |
| Form factor | 1U rack |
| Sockets | 2 |
| CPU | AMD EPYC 7002 / 7003 |
| DIMM slots | 32 |
| Memory | DDR4-3200 RDIMM / 3DS RDIMM, up to 4 TB |
| Storage | Up to 12x 2.5-inch hot-swap SAS/SATA/NVMe or 4x 3.5-inch, M.2 boot |
| RAID | ThinkSystem RAID 530-8i / 930-8i / 9350-8i / 940-8i |
| Management | XClarity Controller (XCC) |
| Released | 2020 |
| Status | previous |
Field notes
EPYC 7003 (Milan) CPUs need UEFI from the 2021 bundle or later, so update before swapping processors. Eight-channel memory per socket means 16 or 32 DIMMs are the sane configs; anything else typically costs bandwidth. Firmware via XCC web UI, OneCLI or XClarity Administrator. ESXi 8, Windows Server 2022 and RHEL 9 are supported; good value on the used market for VM density.
Successor: ThinkSystem SR645 V3.
What we do with the ThinkSystem SR645
- Specification and procurement of ThinkSystem servers
- Rack installation, XCC setup and UEFI/firmware baseline
- Memory, NVMe and RAID upgrades with qualified parts
- Out-of-warranty repair and spare sourcing for System x and ThinkServer
- OS and hypervisor installs
- Lenovo support case handling and refresh planning
Related models
Related services
Frequently asked questions
Is Lenovo a good alternative to Dell?
Yes. ThinkSystem servers are equally reliable, often priced sharply, and XClarity management is mature. We support both and recommend whichever fits the existing fleet.
Can you still service System x servers?
Yes. System x M5 and X6 systems are legacy but parts are available and we keep them running while planning a replacement.
Can the ThinkSystem SR645 run a current operating system?
Check the field notes above. As a rule, current models are certified for Windows Server 2022/2025, ESXi 8 and RHEL 9; legacy models usually stop at Windows Server 2019 or ESXi 7 and may need Proxmox or an older Linux to stay useful.
Need a hand with this?
Tell us what you are running and what is slowing you down. You get a straight assessment and a plan, with no obligation. Support desk is staffed 24/7.