NVIDIA MCX4621A-ACAB ConnectX-4 Lx EN Network Adapter (OCP 3.0)
Overview
The MCX4621A-ACAB is an NVIDIA ConnectX-4 Lx EN network interface card built on the OCP 3.0 form factor. It's designed as an Ethernet network adapter (EN) for server and data center deployments that standardize on the Open Compute Project's OCP 3.0 card specification rather than a traditional PCIe bracket card. The ConnectX-4 Lx family targets server-side network connectivity for enterprise and hyperscale infrastructure, and the OCP 3.0 physical format is specifically intended for tool-less installation in servers built around that mezzanine standard.
Key Features
- OCP 3.0 form factor: Matches server chassis designed around the Open Compute Project 3.0 card specification, which typically means front-serviceable, tool-less card swaps instead of opening the chassis to reach a rear PCIe slot — a real time-saver for data center technicians doing hardware refreshes across racks.
- ConnectX-4 Lx EN architecture: Part of NVIDIA's ConnectX-4 Lx Ethernet-only adapter line, positioned for server network connectivity in environments that need dedicated Ethernet uplink hardware rather than a fabric-converged card.
- Compact card weight (0.24 lb): A lightweight card profile consistent with the OCP 3.0 mezzanine format, which matters when you're racking density-focused servers where every gram and every millimeter of clearance is budgeted.
Integration & Compatibility
Because the MCX4621A-ACAB uses the OCP 3.0 connector and mechanical spec rather than a standard PCIe bracket, confirm your server chassis has an OCP 3.0 mezzanine slot before ordering — this card is not a drop-in replacement for a PCIe-bracket ConnectX-4 Lx variant. If you're standardizing a fleet on NVIDIA networking hardware, pair procurement of the MCX4621A-ACAB (sometimes searched as MCX4621A ACAB) with your broader network switch refresh so port speeds and cabling are matched end to end before install day. For teams still mapping out rack-level connectivity requirements, a network planning guide is a useful reference before committing to a specific adapter SKU.
Frequently Asked Questions
Q: What form factor is the MCX4621A-ACAB?
A: It ships in the OCP 3.0 form factor, not a standard PCIe bracket card, so it requires a server chassis with an OCP 3.0 mezzanine slot.
Q: Is the MCX4621A-ACAB an Ethernet or InfiniBand adapter?
A: It's an EN (Ethernet Networking) variant of the ConnectX-4 Lx family, built for Ethernet connectivity.
Q: How much does the MCX4621A-ACAB weigh?
A: The card weighs 0.24 lb.
Q: Can the MCX4621A-ACAB be installed in a standard PCIe slot?
A: No — it uses the OCP 3.0 connector and mechanical specification, which requires a chassis built for OCP 3.0 cards rather than a conventional PCIe bracket slot.
The MCX4621A-ACAB is the OCP 3.0 flavor of NVIDIA's ConnectX-4 Lx EN adapter, and the form factor decision is really the whole story on this card — it's built for chassis that standardized on the Open Compute Project's tool-less mezzanine slot instead of a rear PCIe bracket.
Technical Highlights:
- OCP 3.0 mechanical spec: Tool-less front-serviceable installation for racks already built around the OCP 3.0 standard — no chassis teardown for a card swap.
- ConnectX-4 Lx EN silicon: Ethernet-only variant of the ConnectX-4 Lx line, aimed at dedicated server network uplinks.
- 0.24 lb card weight: A light, compact package consistent with mezzanine-format cards designed for dense server deployments.
Deployment Considerations:
- Verify OCP 3.0 slot presence and connector orientation on your target server before ordering — this card will not fit a standard PCIe bracket chassis.
- Published evidence for this listing doesn't include port count, link speed, or PCIe generation, so confirm those details against your server's exact interoperability requirements before committing to a large order.
Reach for the MCX4621A-ACAB when you're standardizing a server refresh on OCP 3.0 chassis and need a ConnectX-4 Lx EN adapter that matches that specific mezzanine slot — model number MCX4621A-ACAB, no adapter bracket required.
