The NVIDIA/Mellanox MCA7J65-N001 is a 2x 400Gb/s twin-port OSFP (Octal Small Form-factor Pluggable) IHS/finned top to dual 400G QSFP112 (Quad Small Form-factor Pluggable 112G) active direct attached copper breakout cable. The ACC contains eight high-speed electrical copper pairs, each operating at data rates of up to 100Gb/s using 100G-PAM4 modulation. It complies with IEEE 802.3ck, CMIS 5.0, OSFP Rev 5.0 and Q112 MSA standards.
The OSFP end has a IHS/finned top for additional cooling, while the QSFP112 end is without cooling fins on top and uses the cooling fins located on the adapter cages. It is primarily used to link an 800Gb/s Spectrum-4 switch to two QSFP112-based 400Gb/s ConnectX-7.
ACC cables integrate a redriver chip that extends reach up to 5 meters while ensuring latency, enhancing port bandwidth, density, and configurability. These power-efficient links are ideal for medium-distance connectivity in data centers, AI/HPC clusters, and cross-rack deployments.
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.






