Lenovo 01KR621 — ThinkSystem Mellanox ConnectX-4 VPI FDR 1-Port QSFP28 Adapter
Technical Identity
The Lenovo 01KR621 is a ThinkSystem-branded NVIDIA Mellanox ConnectX-4 VPI dual-protocol network adapter with a single QSFP28 port that operates as either InfiniBand FDR (56 Gb/s) or Ethernet (40 GbE / 56 GbE). PCIe 3.0 ×8 host interface. Lenovo OEM firmware qualified for ThinkSystem rack and tower servers. Condition: Refurbished Grade A — EEPROM-verified, link-tested, EU warehouse stock.
Specifications

Brand / OEM: Lenovo (ThinkSystem qualified) — underlying ASIC: NVIDIA Mellanox ConnectX-4 VPI
Lenovo FRU / PN: 01KR621
ASIC family: ConnectX-4 (MT27700-class)
Product type: VPI dual-protocol network adapter (InfiniBand + Ethernet)
Ports: 1× QSFP28 port
InfiniBand rate: FDR — 56 Gb/s (14 GT/s × 4 lanes)
Ethernet rate: 40 GbE and 56 GbE (Mellanox-to-Mellanox)
Host interface: PCIe 3.0 ×8
Offloads: RoCE v1 / v2, InfiniBand Verbs, RDMA, SR-IOV hardware virtualization, hardware overlay (VXLAN / NVGRE / GENEVE)
Form factor: Standard PCIe HHHL card
Server qualification: Lenovo ThinkSystem (SR530, SR550, SR570, SR590, SR630, SR650, SR850, SR860, SR950, ST550 and similar generations)
Condition: Refurbished Grade A

What This Is NOT

NOT EDR or HDR. Maximum InfiniBand rate is FDR (56 Gb/s). For EDR (100 Gb/s) use ConnectX-4 EDR / ConnectX-5; for HDR (200 Gb/s) use ConnectX-6.
NOT 100 GbE. Ethernet operation caps at 40 / 56 GbE on this FDR SKU. ConnectX-4 EDR or newer SKUs are required for 100 GbE.
NOT dual-port. Single QSFP28 port only — for dual-port FDR use the dual-port ConnectX-4 VPI equivalent.
NOT Lx. ConnectX-4 Lx is Ethernet-only. This SKU is full ConnectX-4 VPI (IB + Ethernet dual-protocol).
NOT a generic NVIDIA retail card. Lenovo OEM firmware — Lenovo XClarity / UpdateXpress is the supported firmware path for ThinkSystem deployments.
NOT supplied with QSFP28 / QSFP+ optical modules, DAC cables, or AOC cables.

Compatibility & Constraints

Primary platform: Lenovo ThinkSystem rack and tower servers. The card will physically operate in any standard x86 PCIe 3.0 ×8 (or wider) slot, but Lenovo OEM firmware may restrict advanced features or block firmware updates outside ThinkSystem chassis — validate before deploying in non-Lenovo hosts.
InfiniBand fabric: FDR — interoperates with Mellanox SwitchX-2 / Switch-IB FDR switches (SX6036, SX6512, SX6710, SX6790, IS5030, IS5035) and with ConnectX-3 / ConnectX-3 Pro / ConnectX-4 FDR endpoints. Auto-negotiates down to QDR on legacy fabrics.
Ethernet fabric: 40 GbE on standard QSFP+ switches (Spectrum-1, SwitchX-2, generic 40 GbE); 56 GbE is supported only on Mellanox-to-Mellanox FDR links.
Cabling: QSFP28 socket accepts QSFP+ DAC / AOC / optics (FDR / 40 GbE) and QSFP28 DAC / AOC (forward-compatible). Use FDR-rated copper for runs under 5 m or FDR AOC for longer reaches.
Software stack: MLNX_OFED / DOCA-Host on Linux; WinOF-2 on Windows Server; Lenovo XClarity / UpdateXpress for firmware updates inside ThinkSystem chassis.

Frequently Asked Questions (FAQ)
Q. What is the Lenovo 01KR621?
A ThinkSystem-branded Mellanox ConnectX-4 VPI dual-protocol adapter with one QSFP28 port. Operates as InfiniBand FDR (56 Gb/s) or Ethernet (40 / 56 GbE) on a PCIe 3.0 ×8 host interface. Lenovo OEM firmware qualified for ThinkSystem servers.
Q. What InfiniBand speed does the 01KR621 support?
FDR only — 56 Gb/s effective. For EDR (100 Gb/s) or HDR (200 Gb/s) other ConnectX generations (ConnectX-4 EDR, ConnectX-5, ConnectX-6) are required.
Q. Can the 01KR621 be used outside a Lenovo ThinkSystem server?
Often yes — the underlying ConnectX-4 silicon is standard. However Lenovo OEM firmware may restrict advanced features or refuse firmware updates outside ThinkSystem platforms. Validate in your target host before production deployment.
Q. What offloads does the 01KR621 support?
RoCE v1 / v2, InfiniBand Verbs, RDMA, SR-IOV hardware virtualization, and hardware overlay encapsulation (VXLAN, NVGRE, GENEVE).
Q. What condition does T.E.S IT-SOLUTIONS supply?
Refurbished Grade A — every unit is MPN-identified, EEPROM-verified, link-tested where possible, and cosmetically inspected before leaving the EU warehouse.
Why buy from T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS is a Europe-based data-center networking specialist. Every Lenovo OEM card we ship is MPN-identified, EEPROM-verified, and cosmetically inspected before leaving our EU warehouse. Multi-currency invoicing (EUR / USD / GBP), DHL / FedEx worldwide express shipping, and free pre-sale technical consultation are included on every B2B order.