NVIDIA Mellanox MCP7F00-A03A 100GbE QSFP28 to 4x25GbE SFP28 Splitter Cable, 3m: This is a 3-meter passive copper Direct Attach Breakout Cable (DAC) that splits a single QSFP28 100GbE port into four independent 25GbE SFP28 connections. This is a passive hybrid cable; it is NOT an active copper cable or an AOC and contains no signal-conditioning electronics. This is a new unit.
Engineering Context
The MCP7F00-A03A enables a single 100GbE QSFP28 switch port to serve four 25GbE SFP28 server endpoints. 100GbE QSFP28 uses 4 lanes of 25Gb/s NRZ; each SFP28 leg carries one of those lanes as a 25GbE link. Passive copper draws essentially zero port power and adds only copper-propagation latency, with no electrical-to-optical conversion overhead. RS-FEC settings should match between the 100GbE switch port (CR4) and the 25GbE endpoints (CR) for stable links.
Deployment & Use Cases
Top-of-Rack 100GbE Spectrum SN2000/SN3000 switch port fanning out to four 25GbE servers in the same rack. ConnectX-4 Lx, ConnectX-5, or ConnectX-6 Dx EN 25GbE adapter to upstream switch via shared 100GbE uplink. Hyperconverged and storage clusters that consolidate 4x25GbE servers into one switch port. Lab and pre-production environments that mix 100GbE switching with 25GbE compute.
Technical Specifications
OEM: NVIDIA Mellanox
Part Number: MCP7F00-A03A
Form Factor: QSFP28 to 4x SFP28
Data Rate: 100GbE to 4x 25GbE
Cable Type: Passive Copper Hybrid Breakout (DAC)
Length: 3m
Protocol: 100GbE / 25GbE Ethernet
Standard: IEEE 802.3bj (100GBASE-CR4), 802.3by (25GBASE-CR)
FEC: RS-FEC support recommended end-to-end
Condition: New — Sealed by T.E.S IT-SOLUTIONS
Compatibility & Hard Constraints
Compatible with NVIDIA Spectrum SN2000 and SN3000 Ethernet switches and ConnectX-4, ConnectX-5, and ConnectX-6 Dx EN adapters. The QSFP28 port must support 4x25G breakout mode; not all 100GbE switches enable this mode on every cage. The four SFP28 legs must each terminate at 25GbE-capable ports. Not compatible with 40GbE QSFP+ ports or 10GbE SFP+ ports. Not designed for InfiniBand fabrics. Fixed 3m length and 1-to-4 ratio; cannot be reconfigured.
Why Choose T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS tests every breakout cable for connector retention, conductor continuity, and EEPROM readout on all four legs before shipment. We offer expert consultation on 100GbE-to-25GbE fan-out design, global shipping, 1-3 day handling, and comprehensive warranty.