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Green PCIe card with dual SFP28 ports and silver bracket

BFKK

BFKK MCX512A-ADAT ConnectX PCIe 4.0x8 25Gbit Dual SFP28 Network Adapter

SKU CH-GKJ2-WGCQD

Dual-port 25 Gbit network adapter with PCIe 4.0 x8 interface and SFP28 connectors

  • Dual-port 25 Gbit throughput for high-bandwidth server links
  • PCIe 4.0 x8 interface delivers low-latency connectivity
  • ConnectX-5 controller accelerates packet processing
  • SFP28 cages support 25 Gbit transceiver modules
  • Mellanox engineering ensures enterprise-grade reliability

Dual-port 25 Gbit server adapter

This Mellanox ConnectX-5 card delivers two SFP28 ports running at 25 Gbit each over a PCIe 4.0 x8 link. It targets datacentre and high-performance computing clusters that need low-latency Ethernet connectivity. The half-height bracket fits standard rackmount servers and workstations. Buyers needing Fibre Channel or InfiniBand protocols should look elsewhere.

Passive cooling for quiet racks

The board uses a passive heatsink so it adds no fan noise and draws power only from the slot. Typical draw stays within the PCIe 4.0 x8 envelope, leaving headroom for other expansion cards. Dense 1U chassis benefit from the zero-airflow requirement. Installations that demand active airflow across the PCB will need supplemental case fans.

PCIe 4.0 x8 slot and SFP28 optics required

A free PCIe 4.0 x8 slot (or wider) supplies both bandwidth and power without extra cables. You must supply compatible SFP28 transceivers or direct-attach cables for each port. The low-profile bracket frees full-height slots for GPUs or storage controllers. Systems limited to PCIe 3.0 x8 will negotiate down to lower throughput.

How it compares

Measured against everything we stock in Ethernet Cards & NICs, at today’s prices. Recalculated every night.

Price $788.99
Pricier than about 90% of the 1,505 comparable items (median $90.99).

Specifications

No published specifications for this item yet.

Questions about this item

How do I install the ConnectX MCX512A-ADAT in a PCIe 4.0 x8 slot and which step is often missed?

Insert the card firmly into a PCIe 4.0 x8 slot, secure the bracket screw, then attach compatible SFP28 modules to both ports before cabling — skipping the module insertion is the common oversight.

What maintenance or replacement will the MCX512A-ADAT need over time?

The adapter itself has no moving parts; plan to replace SFP28 transceivers or cables if link errors appear, and keep the slot and port cages free of dust.

What limit appears first on the MCX512A-ADAT under sustained 25 Gbit traffic?

Each SFP28 port is rated at 25 Gbit/s, so the port line rate is the first ceiling you reach during continuous full-duplex load.

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