Lenovo 02YG091 — ThinkSystem Mellanox ConnectX-5 EN 10/25GbE SFP28 2-Port PCIe Adapter
Technical Identity
Lenovo ThinkSystem-branded Mellanox ConnectX-5 EN dual-port Ethernet adapter, qualified for ThinkSystem rack and tower servers. Two SFP28 cages negotiating 10GbE or 25GbE, PCI Express Gen3 x16 host interface. Hardware-accelerated RoCE v2 (RDMA over Converged Ethernet) for low-latency storage and HPC fabrics, NVMe-over-Fabrics target/initiator offload, VXLAN/NVGRE/Geneve overlay encapsulation, SR-IOV for virtualised tenants, and ASAP² Direct kernel-bypass switching. Condition: Refurbished Grade A — EEPROM-verified, link-tested.
Specifications

Lenovo PN: 02YG091
ASIC: NVIDIA Mellanox ConnectX-5 EN
Ports: 2 × SFP28 (10GbE / 25GbE auto-negotiating)
Host interface: PCI Express 3.0 x16
Form factor: Low-profile PCIe (full-height bracket included)
Protocol: Ethernet only (EN ASIC variant)
Offloads: RoCE v2, NVMe-oF, VXLAN / NVGRE / Geneve, SR-IOV, ASAP² Direct, OVS offload, T10-DIF, TCP/UDP/IP stateless
OEM qualification: Lenovo ThinkSystem (SR-series, ST-series)
Condition: Refurbished Grade A
Warranty: T.E.S 12-month limited

What This Is NOT

NOT InfiniBand capable. EN variant is Ethernet-only — no IB SDR/QDR/FDR/EDR.
NOT 100GbE. Maximum 25GbE per SFP28 port.
NOT a single-port card. Always dual-port.
NOT a standard NVIDIA retail MCX-series card. Lenovo OEM firmware — may behave differently than a generic ConnectX-5 in non-ThinkSystem hosts.
NOT QSFP28. Connectors are SFP28 only.

Compatibility
Host servers: Lenovo ThinkSystem SR530, SR550, SR570, SR590, SR630, SR650, SR670, SR850, SR860, SR950, ST550, ST650 (per Lenovo PSREF). May also run in third-party servers — feature subset depends on Lenovo firmware policy.
Switch fabrics (10/25GbE Ethernet): NVIDIA Spectrum / Spectrum-2 / Spectrum-3 (SN2010, SN2100, SN2410, SN2700, SN3700), Cisco Nexus 9000 / 93180YC, Arista 7050X / 7280SR / 7060X, Juniper QFX5100 / QFX5120, Dell PowerSwitch S5200-ON / S5232F-ON.
Cabling: SFP28 25GbE DAC (MCP2M00-A0xx series), 25GbE AOC (MFA2P10-Axxx series), SFP+ 10GbE DAC/AOC (10G fallback), SR/LR SFP28 optical transceivers (MMA2P00-AS, MMA2L20-AR).
Operating systems: RHEL / Rocky / AlmaLinux 7–9, Ubuntu 18.04–24.04, SLES 12–15, VMware ESXi 6.7–8.0, Windows Server 2016 / 2019 / 2022, Microsoft Azure Stack HCI.
FAQ
Q: What is the Lenovo 02YG091?
A: ThinkSystem-branded Mellanox ConnectX-5 EN dual-port 10/25GbE SFP28 PCIe Ethernet adapter, Lenovo OEM. Supports RoCE v2, NVMe-oF, VXLAN/NVGRE, and SR-IOV.
Q: Does 02YG091 support both 10GbE and 25GbE?
A: Yes. Each SFP28 port auto-negotiates 10GbE or 25GbE. Final speed depends on the switch port configuration and the SFP28/SFP+ cable or transceiver used.
Q: Is 02YG091 InfiniBand capable?
A: No. The EN variant is Ethernet-only. For InfiniBand or VPI dual-protocol on ConnectX-5, choose the MCX556A-EDAT (VPI) or equivalent IB-capable SKU.
Q: Can 02YG091 run in non-Lenovo servers?
A: Mechanically and electrically yes — it is a standard PCIe Gen3 x16 card — but Lenovo OEM firmware may restrict some features or refuse to load on non-ThinkSystem platforms. Validate in a test bench before production deployment.
Q: What condition does T.E.S supply?
A: Refurbished Grade A. Every unit is MPN-verified, EEPROM-checked, link-tested at 25GbE, and cosmetically inspected. Shipped from our EU warehouse with worldwide express options.
Why buy from T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS is a Europe-based data-center networking specialist. Every Lenovo 02YG091 is MPN-identified, EEPROM-verified, link-tested at 25GbE, and cosmetically inspected before leaving our EU warehouse. Multi-currency invoicing (EUR / USD / GBP / ILS), worldwide express shipping, and free pre-sale technical consultation included. Bulk-quote pricing on request for rack-scale ThinkSystem refresh projects.