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Green printed circuit board with two QSFP+ cages and a full-height PCIe x16 bracket

Solarflare Communications, Inc.

Solarflare Communications, Inc. SFN8542-PLUS 40Gbps dual port PCIe 3.1 x16 QSFP+ network card

SKU CH-AJN5-Z2273

Dual-port 40Gbps QSFP+ server adapter using a PCIe 3.1 x16 slot for high-throughput networking

  • Speed40Gbps
  • InterfacePCI-Express
  • 40 Gbps throughput for high-bandwidth workloads
  • Dual QSFP+ ports double aggregate bandwidth
  • PCIe 3.1 x16 interface removes host-bus bottlenecks
  • Solarflare firmware accelerates virtualised server traffic
  • Brand-new condition ensures full factory specifications

Solarflare 40Gbps dual-port QSFP+ adapter

The Solarflare SFN8542-PLUS is a dual-port 40Gbps Ethernet server adapter built for virtualised data-centre workloads. It targets administrators who need high-throughput, low-latency connectivity for dense virtual machine deployments. The card plugs into a PCI Express 3.1 x16 slot and presents two QSFP+ cages for fibre or direct-attach copper links.

PCIe 3.1 x16 slot frees two 40GbE ports

Installation requires an open PCI Express 3.1 x16 slot capable of supplying the adapter’s power envelope. The x16 electrical interface removes bandwidth contention that narrower slots introduce at 40Gbps line rate. Dual QSFP+ ports consolidate two high-speed uplinks into a single add-in card, leaving additional expansion slots available for storage or compute accelerators.

QSFP+ cages accept optics or DAC cables

The two QSFP+ cages accept standard 40GbE transceivers or direct-attach copper cables, letting the installer match reach and cost to the rack layout. No proprietary cabling or licence dongles are bundled; the adapter relies on in-box driver support from current Linux and Windows Server kernels. Solarflare’s userspace stack is available separately for applications that bypass the kernel network path.

Highlights

  • 40 Gbps throughput for high-bandwidth workloads
  • Dual QSFP+ ports double aggregate bandwidth
  • PCIe 3.1 x16 interface removes host-bus bottlenecks
  • Solarflare firmware accelerates virtualised server traffic
  • Brand-new condition ensures full factory specifications

Specifications

BrandSolarflare
Part NumberSFN8542-PLUS
Speed40Gbps
InterfacePCI-Express

Questions about this item

Will the PCIe 3.1 x16 slot saturate at 40 Gbps per port under sustained load?

Each port runs at 40 Gbps and the x16 lane provides enough bandwidth for both ports simultaneously.

What is the typical power draw and thermal output when the adapter runs continuously?

Solarflare designs this adapter for lowest power consumption in its class, keeping heat and fan noise minimal in server chassis.

Which QSFP+ transceivers or direct-attach cables must I already have to connect the two ports?

The card accepts any standard QSFP+ module or DAC, so you need compatible 40 Gbps optics or copper cables for each port.

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