NVIDIA/Mellanox MMS4X00-NM (980-9I30G-00NM00) Compatible 800G 2xDR4 OSFP IHS/Closed Finned Top 8x100G PAM4 1310nm 500m SMF DOM Dual MPO-12/APC InfiniBand NDR Optical Transceiver Module

OSFP-800G-2DR4L-IB: Frequently Asked Questions

Q: What is the difference between the OSFP-800G-2xSR4 and OSFP-800G-2DR4L optical transceiver modules?

A: The main differences are their optical interfaces, fiber types, and transmission distances. The OSFP-800G-2xSR4H uses two 400G SR4 multimode optical interfaces, typically operating at 850nm over multimode fiber. The OSFP-800G-2DR4L uses two independent 400G DR4 single-mode optical interfaces, operating at 1310nm with a reach of up to 500m over single-mode fiber. Both use a Twin-Port OSFP design, but they require different fiber infrastructure and optical connectivity. Always verify the host platform and port configuration before deployment.

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Q: What is the difference between Finned Top and Flat Top OSFP modules?

A: Finned Top and Flat Top refer to different thermal and mechanical designs. A Finned Top module features heat-dissipation fins on its upper surface to improve heat transfer in systems designed for this cooling interface. A Flat Top module has a flatter upper profile and is commonly used in platforms with more restricted module clearance, such as certain NIC and adapter configurations. The OSFP-800G-2DR4L features a Closed Finned Top design for compatible air-cooled switch platforms. Always check the host device’s mechanical and thermal requirements before selecting the module type.

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Q: Can the NVIDIA/Mellanox MMS4X00-NM compatible 800G 2xDR4 OSFP module work with NVIDIA QM9700 and QM9790 switches?

A: This module is designed for compatible NVIDIA QM9700 and QM9790 switch configurations. It supports an 800G Twin-Port 2xDR4 optical architecture with two independent 400G DR4 interfaces. Each module is functionally and optically tested before shipment, and corresponding test documentation can be provided upon request. Actual interoperability depends on the switch hardware, OSFP port configuration, and firmware version.

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Q: Can I use only one optical port on the 800G Twin-Port 2xDR4 OSFP module?

A: Yes. The module has two independent 400G DR4 optical interfaces. If only one optical interface is enabled and supported by the host platform, it can operate at 400Gb/s while the other interface remains unused. The actual operating mode depends on the host switch configuration and supported firmware.

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Q: Can a 400G OSFP optical transceiver be installed in an 800G OSFP port?

A: A 400G OSFP module may be physically compatible with an 800G OSFP cage, but successful operation is not guaranteed by the form factor alone. The host switch must support 400G operation, the module’s optical interface, and the corresponding firmware and port configuration. Please verify the device compatibility matrix and port capabilities before deployment.

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Q: What fiber and connectors are required for the 800G 2xDR4 OSFP module?

A: The module uses two independent MPO-12/APC optical connectors, one for each 400G DR4 interface. It operates over single-mode fiber at 1310nm, supporting a transmission distance of up to 500m under the specified optical link conditions. Use compatible MPO-12/APC single-mode fiber assemblies and verify connector polarity and fiber mapping at both ends of the link.

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Q: What is the difference between 800G 2xDR4 and 800G DR8 optical transceivers?

A: Both architectures can support an aggregate bandwidth of 800Gb/s using eight 100G PAM4 lanes, but their optical interfaces are different. An 800G 2xDR4 module has two independent 400G optical interfaces, each using a four-lane DR4 link and a separate MPO-12/APC connector. An 800G DR8 module uses a single eight-lane 800G optical interface, typically with an MPO-16 connector. They are not directly interchangeable and require matching optical interfaces, fiber assemblies, and host configurations.