The HP 649281-B21 is an HP OEM ConnectX-3 VPI dual-port QSFP network adapter supporting InfiniBand FDR at 56Gb/s and 40GbE Ethernet (Virtual Protocol Interconnect). Two QSFP ports. PCIe 3.0 x8. HP branded for HP ProLiant server environments. The underlying adapter is manufactured by Mellanox (ConnectX-3 VPI) and carries HP part number 649281-B21 for compatibility with HP ProLiant servers and HP firmware management tools. This adapter IS a dual-protocol (VPI) QSFP NIC supporting both InfiniBand FDR and 40GbE. It is NOT Ethernet-only, NOT InfiniBand-only, and NOT a QSFP28 (100GbE) card. This is original HP-branded Mellanox hardware sold by T.E.S IT-SOLUTIONS (tes-itsolutions.com). Condition: refurbished.
Engineering
The HP 649281-B21 (ConnectX-3 VPI) provides up to 56Gb/s per port in InfiniBand FDR mode (4x14Gb/s lanes) or 40Gb/s per port in 40GbE Ethernet mode. Dual QSFP ports. PCIe 3.0 x8 host interface. VPI architecture allows each port to be independently configured for InfiniBand or Ethernet mode via firmware. The adapter is the HP OEM variant of the Mellanox MCX354A-FCBT ConnectX-3 VPI. Supports RDMA over InfiniBand and RoCE v1 for Ethernet mode.
Deployment
Used in HP ProLiant server environments for FDR InfiniBand HPC cluster connectivity and 40GbE data center networking. Common in ProLiant BL460c blade systems and DL-series rack servers requiring InfiniBand fabric connectivity alongside standard Ethernet. Supports mixed InfiniBand + Ethernet deployments (VPI mode). Also deployed in non-HP environments where a dual-port ConnectX-3 VPI QSFP adapter is required — the HP OEM branding does not restrict functionality on non-HP hardware, though HP-specific firmware tools (HPE OneView, Smart Array) will not recognize the card outside ProLiant.
Specifications
HP Part Number: 649281-B21
OEM: HP (Hewlett Packard)
Underlying Adapter: Mellanox ConnectX-3 VPI
Data Rate: 56Gb/s IB FDR per port / 40GbE per port
Port Count: 2
Connector: QSFP (both ports)
Host Interface: PCIe 3.0 x8
Protocol: VPI — InfiniBand FDR + 40GbE Ethernet
InfiniBand Generation: FDR (56Gb/s)
Condition: Refurbished
Compatibility
Compatible with HP ProLiant DL, BL, and ML servers. Compatible with FDR InfiniBand QSFP switches: Mellanox SX6036, IS5100. Compatible with 40GbE QSFP switches: Mellanox SN2100 series. Compatible with QSFP DAC cables and active optical cables. NOT compatible with QSFP28 (100GbE) cables — this is a QSFP (not QSFP28) adapter. NOT compatible with EDR (100Gb/s) or HDR (200Gb/s) InfiniBand. For EEPROM compatibility outside HP environments, confirm with switch/HCA firmware before deployment. HP 570FLB (652503-B21) is the FlexibleLOM equivalent for HP servers requiring LOM-form adapters instead of PCIe.
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS is a European reseller specializing in original and refurbished enterprise networking hardware including HP OEM Mellanox adapters, NVIDIA Mellanox switches, and ConnectX series NICs, operating since 2011. Each HP 649281-B21 is tested for PCIe link negotiation and port activity before shipment. Global shipping with 1–3 business day handling.