The NVIDIA/Mellanox MCP4Y10-N00A-FLT Compatible cable is a 2x 400Gb/s twin-port OSFP IHS/finned top to 2x 400Gb/s twin-port OSFP RHS/flat top direct attached copper cable. The DAC features eight high-speed electrical copper pairs, each operating at up to 100Gb/s using PAM4 modulation. It complies with OSFP MSA, IEEE 802.3ck and CMIS 5.0 standards.
The OSFP end has a IHS/finned top for additional cooling, while the other OSFP end is RHS/flat top and relies on the host cage for heat dissipation. It is primarily used to connect an 800Gb/s Quantum-2 InfiniBand switch to the DGX H100 system or ConnectX-8 NICs.
DAC cables are the lowest-cost, lowest-latency, near-zero-power-consuming high-speed links available due to their simplicity of design and minimal components. They are ideal for short-distance interconnections within telecom or data center equipment rooms, offering a power-efficient and cost-effective connectivity solution.
Note: "Finned top" transceivers are now called "Integrated Heat Sink" (IHS) as the cooling fins are integrated into the OSFP connector metal top. Commonly used in air-cooled switches.
"Flat top" transceivers are now called "Riding Heat Sink" (RHS) as the cooling fins ride on top of the network card or system's internal cages. This is used for both air-cooled and liquid-cooled applications for DGX, ConnectX-7, and BlueField-3 DPUS.
