400G Ethernet
400G Ethernet Switching, Adapters and Optics
400G is where AI and storage fabrics are landing, and it is the speed at which the cabling decision stops being an afterthought. Passive copper is cheapest and lowest-power but stops at a few metres; active optical carries further with no separate optic to buy; a transceiver pair plus structured fibre is the only option once you leave the rack row.
Everything on this page runs at 400G or above: Arista 7060DX4-32 and 7280CR3-32P4 switching, the ConnectX-7 400GbE OSFP adapter and BlueField-3 B3140H DPU, NVIDIA-coded SR8, DR4, FR4 and 800G OSFP modules, QSFP-DD DAC from 0.5m to 5m, AOC from 3m to 30m, and 400G-to-4x100G breakout leads for nodes not yet at 400G.
Both connector systems are here — QSFP-DD on the Arista, Dell, HPE and Juniper side, OSFP on the NVIDIA side — because which one you need is decided by the switch and the adapter, not by preference. We check the pairing before anything ships.
61 configurations below · quotes returned within 48 business hours · purchase orders accepted
400G Ethernet Switching, Adapters and Optics we configure and supply
Every system below is quoted to your workload — accelerator count, CPU, memory, storage and fabric are specified together rather than sold as a fixed SKU.
Arista 7280CR3-32P4 32 x 100GbE QSFP28 + 4 x 400GbE QSFP-DD Deep Buffer Spine and Edge Switch
Deep-buffer switching for spine and WAN edge, where microbursts would otherwise drop.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 7060DX4-32 32 x 400GbE QSFP-DD Layer 3 Data Center Spine Switch
Low-latency spine switching for AI cluster and leaf-spine fabrics.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA ConnectX -7 400GbE Single-Port OSFP Ethernet Network Adapter Card
SmartNIC with RoCE and hardware offload for storage and AI fabrics.
- Authorized supply
- Compatibility checked
- Volume pricing
400G QSFP-DD SR8 850nm 100m Optical Transceiver Module
Data center optic for switch-to-server and switch-to-switch links.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA 400G QSFP-DD SR8 850nm Optical Transceiver Module
The 200G to 800G optics that GPU cluster fabrics run on, coded for Spectrum Ethernet and Quantum InfiniBand.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA 400G QSFP-DD DR4 1310nm Optical Transceiver Module
The 200G to 800G optics that GPU cluster fabrics run on, coded for Spectrum Ethernet and Quantum InfiniBand.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA 400G QSFP-DD FR4 1310nm Optical Transceiver Module
The 200G to 800G optics that GPU cluster fabrics run on, coded for Spectrum Ethernet and Quantum InfiniBand.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA 400G OSFP SR8 850nm Optical Transceiver Module
The 200G to 800G optics that GPU cluster fabrics run on, coded for Spectrum Ethernet and Quantum InfiniBand.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA 800G OSFP SR8 850nm Optical Transceiver Module
The 200G to 800G optics that GPU cluster fabrics run on, coded for Spectrum Ethernet and Quantum InfiniBand.
- Authorized supply
- Compatibility checked
- Volume pricing
NVIDIA 800G OSFP DR8 1310nm Optical Transceiver Module
The 200G to 800G optics that GPU cluster fabrics run on, coded for Spectrum Ethernet and Quantum InfiniBand.
- Authorized supply
- Compatibility checked
- Volume pricing
Nexus Compute 400G QSFP-DD 1m Passive Direct Attach Copper Cable
In-rack copper for top-of-rack links — no optics, no power draw, lowest latency per link.
- Authorized supply
- Compatibility checked
- Volume pricing
Nexus Compute 400G QSFP-DD 2m Passive Direct Attach Copper Cable
In-rack copper for top-of-rack links — no optics, no power draw, lowest latency per link.
- Authorized supply
- Compatibility checked
- Volume pricing
Nexus Compute 400G QSFP-DD 3m Passive Direct Attach Copper Cable
In-rack copper for top-of-rack links — no optics, no power draw, lowest latency per link.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 400G QSFP-DD 0.5m Passive Direct Attach Copper Cable
Arista-coded twinax for in-rack leaf links, recognised by EOS without a warning.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 400G QSFP-DD 1m Passive Direct Attach Copper Cable
Arista-coded twinax for in-rack leaf links, recognised by EOS without a warning.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 400G QSFP-DD 1.5m Passive Direct Attach Copper Cable
Arista-coded twinax for in-rack leaf links, recognised by EOS without a warning.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 400G QSFP-DD 2m Passive Direct Attach Copper Cable
Arista-coded twinax for in-rack leaf links, recognised by EOS without a warning.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 400G QSFP-DD 3m Passive Direct Attach Copper Cable
Arista-coded twinax for in-rack leaf links, recognised by EOS without a warning.
- Authorized supply
- Compatibility checked
- Volume pricing
Arista 400G QSFP-DD 5m Passive Direct Attach Copper Cable
Arista-coded twinax for in-rack leaf links, recognised by EOS without a warning.
- Authorized supply
- Compatibility checked
- Volume pricing
Juniper 400G QSFP-DD 0.5m Passive Direct Attach Copper Cable
Junos-coded twinax for QFX and EX top-of-rack connections.
- Authorized supply
- Compatibility checked
- Volume pricing
Juniper 400G QSFP-DD 1m Passive Direct Attach Copper Cable
Junos-coded twinax for QFX and EX top-of-rack connections.
- Authorized supply
- Compatibility checked
- Volume pricing
Juniper 400G QSFP-DD 1.5m Passive Direct Attach Copper Cable
Junos-coded twinax for QFX and EX top-of-rack connections.
- Authorized supply
- Compatibility checked
- Volume pricing
Juniper 400G QSFP-DD 2m Passive Direct Attach Copper Cable
Junos-coded twinax for QFX and EX top-of-rack connections.
- Authorized supply
- Compatibility checked
- Volume pricing
Juniper 400G QSFP-DD 3m Passive Direct Attach Copper Cable
Junos-coded twinax for QFX and EX top-of-rack connections.
- Authorized supply
- Compatibility checked
- Volume pricing
All 61 400g ethernet parts we supply
- Juniper 400G QSFP-DD 5m Passive Direct Attach Copper Cable
- HPE 400G QSFP-DD 0.5m Passive Direct Attach Copper Cable
- HPE 400G QSFP-DD 1m Passive Direct Attach Copper Cable
- HPE 400G QSFP-DD 1.5m Passive Direct Attach Copper Cable
- HPE 400G QSFP-DD 2m Passive Direct Attach Copper Cable
- HPE 400G QSFP-DD 3m Passive Direct Attach Copper Cable
- HPE 400G QSFP-DD 5m Passive Direct Attach Copper Cable
- Dell Technologies 400G QSFP-DD 0.5m Passive Direct Attach Copper Cable
- Dell Technologies 400G QSFP-DD 1m Passive Direct Attach Copper Cable
- Dell Technologies 400G QSFP-DD 1.5m Passive Direct Attach Copper Cable
- Dell Technologies 400G QSFP-DD 2m Passive Direct Attach Copper Cable
- Dell Technologies 400G QSFP-DD 3m Passive Direct Attach Copper Cable
- Dell Technologies 400G QSFP-DD 5m Passive Direct Attach Copper Cable
- NVIDIA Networking 400G QSFP-DD 0.5m Passive Direct Attach Copper Cable
- NVIDIA Networking 400G QSFP-DD 1m Passive Direct Attach Copper Cable
- NVIDIA Networking 400G QSFP-DD 1.5m Passive Direct Attach Copper Cable
- NVIDIA Networking 400G QSFP-DD 2m Passive Direct Attach Copper Cable
- NVIDIA Networking 400G QSFP-DD 3m Passive Direct Attach Copper Cable
- NVIDIA Networking 400G QSFP-DD 5m Passive Direct Attach Copper Cable
- Nexus Compute 400G QSFP-DD 3m Active Optical Cable
- Nexus Compute 400G QSFP-DD 5m Active Optical Cable
- Nexus Compute 400G QSFP-DD 7m Active Optical Cable
- Nexus Compute 400G QSFP-DD 10m Active Optical Cable
- Nexus Compute 400G QSFP-DD 15m Active Optical Cable
- Nexus Compute 400G QSFP-DD 20m Active Optical Cable
- Nexus Compute 400G QSFP-DD 30m Active Optical Cable
- NVIDIA Networking 400G QSFP-DD 3m Active Optical Cable
- NVIDIA Networking 400G QSFP-DD 5m Active Optical Cable
- NVIDIA Networking 400G QSFP-DD 10m Active Optical Cable
- NVIDIA Networking 400G QSFP-DD 15m Active Optical Cable
- NVIDIA Networking 400G QSFP-DD 20m Active Optical Cable
- NVIDIA Networking 400G QSFP-DD 30m Active Optical Cable
- Nexus Compute 400G QSFP-DD to 4x QSFP28 1m Passive Direct Attach Copper Cable
- Nexus Compute 400G QSFP-DD to 4x QSFP28 1.5m Passive Direct Attach Copper Cable
- Nexus Compute 400G QSFP-DD to 4x QSFP28 2m Passive Direct Attach Copper Cable
- Nexus Compute 400G QSFP-DD to 4x QSFP28 3m Passive Direct Attach Copper Cable
- Nexus Compute 400G QSFP-DD to 4x QSFP28 5m Passive Direct Attach Copper Cable
What we need to quote accurately
A configuration quote takes minutes when these are known and days of back-and-forth when they are not. You do not need all of them to start — send what you have.
- The workload: model sizes, training or inference, and expected concurrency
- Node count, and whether this is a single system or a scaling cluster
- Rack power and cooling available per rack, and inlet temperature
- Existing estate — the vendor and management tooling you already run
- Network fabric: InfiniBand, Ethernet, and the speed you are standardised on
- Timeline, and whether the budget is approved or being built
How we quote
- 1
Send the requirement
An email, a bill of materials, or a rough description of the workload. All three work.
- 2
We validate the configuration
Accelerator, chassis, fabric, power and cooling checked against each other before anything is priced.
- 3
Itemised quote within 48 hours
Line-by-line pricing, current availability and lead time, with warranty terms stated.
400G Ethernet — buyer questions
Which 400G optic or cable do we need for a given distance?
Passive QSFP-DD DAC covers 0.5m to 5m and is the right answer inside a rack. Active optical cable covers 3m to 30m and suits rack-to-rack runs in the same row. Beyond that you want transceivers on structured fibre: 400G SR8 reaches 100m on OM4 multimode with an MPO connector, DR4 reaches 500m on single-mode OS2, and FR4 reaches 2km on OS2. Give us the rack elevation and we will build the cable schedule against it.
QSFP-DD or OSFP — which do we order?
The port decides. The 400G switches listed here use QSFP-DD, and NVIDIA's 400G and 800G modules plus the ConnectX-7 400GbE adapter use OSFP. They are not interchangeable, and the commonest 400G ordering mistake is buying the module for the far end of the link rather than the near end. Send us both endpoints and we will specify each side.
Can we break a 400G port out to 4x100G?
Yes. We list 400G QSFP-DD to 4x QSFP28 passive breakout cables at 1m, 1.5m, 2m, 3m and 5m, which is how most sites connect 400G spine capacity to nodes still running 100G adapters. Breakout has to be enabled on the switch port group, so confirm the platform supports it on the specific ports you plan to use — we check that as part of the quote.
Do you carry 800G?
Two 800G OSFP modules are in the catalogue — SR8 at 100m on OM4 multimode and DR8 at 500m on single-mode OS2, both NVIDIA Spectrum and Quantum coded. There is no 800G switch in the published catalogue; 800G switching is sourced to order. If you are planning an 800G spine, tell us the platform and we will quote the switching alongside the optics.
Compare with other platforms
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AI Cluster Network Fabric
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