NVIDIA V100 Interconnect Matrix: EDR 100G Cables & Optics
Short answer: NVIDIA V100 systems connect at 100Gb/s: EDR InfiniBand or 100GbE on QSFP28 ports, through ConnectX-4 or ConnectX-5 adapters and EDR switches such as the Switch-IB 2 SB7800. In a rack, use a 100G QSFP28 passive DAC. Beyond that, use 100G SR4 optics over MPO-12 multimode fiber to 100 m. At Resilient Tec the MMA1B00-E100 EDR SR4 optic is $79, the MCP1600-E001E30 EDR DAC is $42 and the R740xd dual-V100 build is $5,849. Prices and stock checked October 12, 2026.
Which Volta system · Link-by-link matrix · Rules · V100 GPUs and servers · FAQ · Shop all Volta-generation parts
Which Volta System Do You Have?
| System | Cluster ports | What plugs in |
|---|---|---|
| DGX-1 with V100 | 4× ConnectX-4 at 100G EDR InfiniBand, QSFP28. | EDR optics (MMA1B00-E100) or EDR QSFP28 DACs (MCP1600-E001E30). |
| DGX-2 and HGX-2 | ConnectX-5 at 100G EDR / 100GbE, QSFP28. | EDR or 100GbE parts, depending on how the adapters are configured. |
| V100 PCIe servers (Dell R740xd, HPE DL380 and others) | Whatever adapter the server has, usually 25G or 100G Ethernet. | 100GbE: MMA1B00-C100D optics or MCP1600-C001 DACs. 25G: MCP7F00-A003 100G → 4× 25G breakout. |
Link-by-Link Matrix
| Link | Reach | Cable or optic | Price |
|---|---|---|---|
| EDR InfiniBand, in-rack copper | Up to 2 m | MCP1600-E00AE30 0.5 m · MCP1600-E001E30 1 m · MCP1600-E002E30 2 m, EDR QSFP28 passive DAC | $39 · $42 · $55 |
| EDR InfiniBand, server → switch, optical | Up to 100 m on OM4 | MMA1B00-E100 100G EDR SR4 at both ends + MPO-12 UPC multimode trunk | $79 each |
| 100GbE, server → switch, optical | Up to 100 m on OM4 | MMA1B00-C100D 100G SR4 at both ends + MPO-12 UPC multimode trunk | $94 each |
| 100GbE, in-rack copper | Up to 1 m (this length) | MCP1600-C001 100G QSFP28 passive DAC | $45 |
| 100G switch port → four 25G servers | Up to 3 m (this length) | MCP7F00-A003 QSFP28 → 4× SFP28 breakout DAC | $125 |
Rules That Prevent Wrong Orders
- E is InfiniBand, C is Ethernet. In Mellanox part numbers, MMA1B00-E100 is EDR InfiniBand and MMA1B00-C100D is 100GbE. Match the code to the port mode. For EDR in-rack copper, use the MCP1600-E DACs; for 100GbE, the MCP1600-C.
- QSFP28 throughout. Volta-era 100G ports are QSFP28. 200G QSFP56 cables are a different generation.
- UPC MPO fiber. 100G SR4 optics use flat-polished MPO-12/UPC cords, not the APC cords made for NDR.
V100 GPUs and Servers
| Item | What it is | Price |
|---|---|---|
| R740xd dual-V100 build | Dell PowerEdge R740xd with two V100 32GB GPUs, enablement kit installed and tested. | $5,849 |
| HPE Q2N68A Tesla V100 PCIe 16GB | Refurbished V100 PCIe accelerator. | $699 |
| Dell VFJ45 V100 16GB | Refurbished passive V100 16GB HBM2. | $699 |
Moving up? The next generations are on the A100 matrix (200G HDR) and the H100 / H200 matrix (400G NDR).
Frequently Asked Questions
What cable does a V100 cluster use? V100 systems connect at 100Gb/s on QSFP28 ports, either EDR InfiniBand or 100GbE. In a rack, use a 100G QSFP28 passive DAC: MCP1600-E for EDR InfiniBand or MCP1600-C for 100GbE. Beyond a few meters, use 100G SR4 optics such as the MMA1B00-E100 (EDR) or MMA1B00-C100D (100GbE) over MPO-12 multimode fiber.
What network does a DGX-1 use? The DGX-1 with V100 has four ConnectX-4 adapters running 100G EDR InfiniBand on QSFP28 ports, normally connected to an EDR switch such as the Switch-IB 2 SB7800.
What is the difference between MMA1B00-E100 and MMA1B00-C100D? Both are 100G QSFP28 SR4 multimode optics. The E100 is coded for EDR InfiniBand and the C100D for 100GbE Ethernet. Use the one that matches how your adapter and switch ports are configured.
Is a V100 still worth buying in 2026? For budget training and inference on models that fit in 16 or 32 GB, yes. A refurbished V100 PCIe is $699 at Resilient Tec. For larger language models, the 48GB A40 is the better value.
Related Guides
- A100 interconnect matrix: the next generation
- H100 / H200 interconnect matrix
- NVIDIA & Mellanox interconnect compatibility guide
- All Volta-generation parts
Last verified October 12, 2026 against NVIDIA LinkX documentation. Every part ships from Knoxville, Tennessee with a lifetime warranty and free US shipping. Questions about a specific build? Talk to an engineer.