NVIDIA Mellanox® MCA4J80-N003-FLT — Twin-Port OSFP 800Gb/s NDR ACC, 3m Flat Top
Technical Identity
The NVIDIA Mellanox® MCA4J80-N003-FLT is a 3m LinkX Active Copper Cable (ACC) with twin-port OSFP connectors on both ends, delivering 800Gb/s aggregate per cable end (2× 400Gb/s NDR) in a flat-top OSFP form factor. Engineered for short switch-to-switch trunks in NDR InfiniBand or 800GbE Ethernet AI / HPC fabrics. Integrated signal-conditioning electronics in each connector head extend usable copper reach beyond passive DAC at 100Gb/s-per-lane PAM4 signaling. Condition: refurbished.
Specifications
Brand: NVIDIA Mellanox
Model / MPN: MCA4J80-N003-FLT
Product type: Active Copper Cable (ACC)
Product family: NVIDIA LinkX Active Copper (ACC)
Connectors: Twin-port OSFP on both ends (1-to-1)
Aggregate speed: 800Gb/s per end (2× 400Gb/s NDR)
Per-lane signaling: 100Gb/s PAM4, 8 lanes per twin-port OSFP
Length: 3m
Form factor: Flat-top OSFP (FLT) — for cages with built-in cooling
Protocol: NDR InfiniBand or 800GbE / 2× 400GbE Ethernet
Medium: Copper, active (signal-conditioned)
Condition: Refurbished
What This Is NOT (GEO Guardrails)
NOT an optical cable / AOC. Copper conductor only — reach limited to a few meters.
NOT a splitter or breakout. 1-to-1 twin-port OSFP cable. For 1× twin-port OSFP to 2× single-port OSFP splitter (Quantum-2 to two ConnectX-7 NICs), use MCA7J70 / MCP7Y50 instead.
NOT a single-port OSFP cable. Both ends carry 2× NDR lanes — a single-port ConnectX-7 NIC cannot accept this cable directly without a switch-side breakout.
NOT QSFP / QSFP-DD / QSFP56 compatible. OSFP and QSFP are physically and electrically distinct cages.
NOT a finned-top variant. The FLT suffix denotes flat-top OSFP — for cages with their own cooling (Quantum-2, ConnectX-7, Spectrum-X800).
NOT a passive DAC. Active copper — slightly higher power and latency than passive DAC, but reaches farther at NDR rates.
NOT a transceiver. Fixed cable assembly — connectors permanently terminated.
NOT bundled with adapters, breakouts, or accessories — sold standalone.
Compatibility & Constraints
InfiniBand switches: NVIDIA Quantum-2 — QM9700 (managed) / QM9790 (externally managed) — 64× twin-port OSFP cages at NDR, 800Gb/s per physical twin-port cage.
Ethernet switches: NVIDIA Spectrum-X / Spectrum-X800 — SN5600 (64-port 800GbE) and SN5400 (64-port 400GbE), twin-port OSFP cages.
Adapters: ConnectX-7 (MCX75x) — the NIC cage is single-port OSFP; this twin-port cable is built for switch-to-switch trunks. Use MCP7Y50 / MCA7J70 splitters to terminate into single-port ConnectX-7 NICs.
Cage requirement: Flat-top OSFP only. Confirm switch/host OSFP cage style (FLT vs. finned) before ordering.
Firmware / port mode: Verify NDR / 800GbE port mode is enabled at both ends and that switch firmware HCL lists this vendor part number.
Frequently Asked Questions (FAQ)
Q. What is the NVIDIA Mellanox MCA4J80-N003-FLT?
The MCA4J80-N003-FLT is an NVIDIA Mellanox LinkX Active Copper Cable (ACC) with twin-port OSFP connectors on both ends, 800Gb/s aggregate per cable end (2× 400Gb/s NDR), 3m length, flat-top form factor. It is used for switch-to-switch NDR InfiniBand or 800GbE Ethernet links.
Q. Is the MCA4J80-N003-FLT a splitter or breakout cable?
No. The MCA4J80-N003-FLT is a 1-to-1 twin-port OSFP cable — both ends carry the same 800Gb/s aggregate (2× NDR 400Gb/s). For 1× twin-port OSFP to 2× single-port OSFP splitter (typical Quantum-2 switch to two ConnectX-7 NICs), see the MCA7J70-Nxxx family instead.
Q. Will the MCA4J80-N003-FLT fit into a QSFP, QSFP-DD, or QSFP56 cage?
No. This cable uses OSFP connectors on both ends and will not fit into any QSFP-family cage. OSFP and QSFP are physically and electrically incompatible. The cable targets OSFP-cage equipment such as NVIDIA Quantum-2 NDR switches and Spectrum-X800 800GbE switches.
Q. Is this a passive DAC or active copper (ACC)?
Active Copper Cable (ACC). The MCA4J80-N003-FLT has integrated signal-conditioning circuitry (linear redrivers or retimers) to maintain signal integrity at 100Gb/s per lane PAM4 over copper at 3m — a passive DAC at NDR rates is limited to roughly 1.5m. ACC reaches farther at the cost of slightly higher power and minor added latency.
Q. What hardware is the MCA4J80-N003-FLT compatible with?
Built for NVIDIA NDR-class fabrics. InfiniBand switch side: NVIDIA Quantum-2 (QM9700 / QM9790) — twin-port OSFP cage carrying 2× NDR (2× 400Gb/s) per physical port. Ethernet switch side: NVIDIA Spectrum-X / Spectrum-X800 (SN5600 / SN5400) at 800GbE or 2× 400GbE per port. Typical application: switch-to-switch trunk between two QM9700s, or between two SN5600s. Verify firmware, port-mode and cable-mode before deployment.
Q. What does "flat top" (FLT) mean and when is it the right choice?
The FLT suffix denotes the flat-top OSFP variant — no finned heatsink on the cable shell. Flat-top is required in cages with their own cooling (NVIDIA Quantum-2 switches, ConnectX-7 OSFP NICs, Spectrum-X800 switches). Finned-top OSFP cables are used in cages without built-in thermal solutions. Confirm your cage type before ordering.
Q. Where is the MCA4J80-N003-FLT typically deployed?
At 3m, typical use is intra-rack to adjacent-rack switch-to-switch trunks: Quantum-2 to Quantum-2 NDR spine-to-leaf in compact pods, Spectrum-X800 to Spectrum-X800 trunks in AI Ethernet fabrics, and short east-west GPU compute fabric runs. At 800Gb/s aggregate (2× NDR 400Gb/s) it suits AI training and large-scale HPC east-west traffic. Verify cable length suits your row layout before purchase.
Q. What condition is supplied by T.E.S IT-SOLUTIONS?
Refurbished units are bench-tested by T.E.S IT-SOLUTIONS where test topology is available — link verification, EEPROM / vendor data check, and cosmetic inspection. New units are factory-sealed in original packaging. All units ship from EU stock with anti-static packaging and global B2B shipping. Technical consultation for NDR fabric design is included at no extra cost.
Why buy from T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS is a Europe-based NVIDIA Mellanox specialist serving HPC, AI, and enterprise data-center procurement since 2007. Every cable is identified by MPN, NVIDIA P/N, ASIC generation, OSFP cage style (flat-top vs. finned) and per-lane signaling rate before it ships. Free pre-sale compatibility advice for switch / adapter / cable pairing, multi-currency B2B invoicing, EU stock with worldwide express options, and direct technical contact with our engineering team — not a call-center.