The network ports of the ConnectX®-4 Lx adapter card are compliant with the IEEE 802.3 Ethernet standards listed in Features and Benefits. Ethernet traffic is transmitted through the SFP28/QSFP28 connectors on the adapter card.


The adapter card includes special circuits to protect from ESD shocks to the card/server when plugging copper cables.

The table below describes the supported PCIe interface in ConnectX-4 Lx adapter cards.

Supported PCIe Interface


PCIe Gen 3.0 (1.1 and 2.0 compatible) through x8 edge connectors

Link Rates: 2.5. 5.0 or 8.0GT/s.

Auto Negotiation to: x8, x4, x2 or x1.

Support for MSI/MSI-X mechanisms.

There is one bi-color I/O LED per port to indicate link status located on the adapter card.

Link Indications (Ethernet Mode)

LED Color and State



A link has not been established

Blinking Amber(a)

4 Hz blinking amber indicates a problem with the link

Solid Green

Indicates a valid link with no active traffic

Blinking Green

Indicates a valid logical link with active traffic

Note a. 1Hz Blinking amber occurs due to running a beacon command for locating the adapter card.

A heatsink is attached to the ConnectX-4 Lx IC in order to dissipate the heat from the ConnectX-4 Lx IC. It is attached either by using four spring-loaded push pins that insert into four mounting holes, or by screws.

ConnectX-4 Lx IC has a thermal shutdown safety mechanism which automatically shuts down the ConnectX-4 Lx card in cases of high-temperature event, improper thermal coupling or heatsink removal.

ConnectX-4 Lx technology maintains support for manageability through a BMC. ConnectX-4 Lx PCIe stand-up adapter can be connected to a BMC using MCTP over SMBus or MCTP over PCIe protocols as if it is a standard NVIDIA PCIe stand-up adapter. For configuring the adapter for the specific manageability solution in use by the server, please contact NVIDIA Support.

The voltage regulator power is derived from the PCI Express edge connector 12V supply pins. These voltage supply pins feed on-board regulators that provide the necessary power to the various components on the card.

© Copyright 2023, NVIDIA. Last updated on Jan 14, 2024.