NVIDIA Mellanox® MCP1660-W01A — 400GbE QSFP-DD Passive Copper DAC, 1.5m, 30AWG
Technical Identity
The NVIDIA Mellanox® MCP1660-W01A (full NVIDIA ordering P/N MCP1660-W01AE30) is a passive direct attach copper cable for 400Gb/s Ethernet, QSFP-DD to QSFP-DD, 1.5m, 30AWG. NVIDIA's ordering description: Direct Attach Copper cable, 400GbE, 400Gb/s, QSFP-DD, 1.5m, 30AWG. The cable carries 16 copper pairs forming 8 electrical lanes at 50Gb/s PAM4 each. Protocol classification: 400GbE Ethernet. Condition: NEW factory stock.
Specifications

Brand: NVIDIA Mellanox
Model / MPN: MCP1660-W01A
NVIDIA ordering P/N: MCP1660-W01AE30
Product type: Passive copper DAC cable
Product family: NVIDIA LinkX MCP1660-W0xx (400GbE)
Connector: QSFP-DD to QSFP-DD (QSFP-DD MSA compliant)
Configuration: 1-to-1, straight cable
Speed: 400Gb/s aggregate
Modulation: 8 lanes x 50Gb/s PAM4
Length: 1.5m
Wire gauge: 30AWG
Protocol: Ethernet (400GbE classification)
Medium: Passive copper twinax, no active electronics
Management: EEPROM per connector, SFF-8636 compliant I2C interface
Power consumption: max 0.1W
Operating case temperature: 0°C to 70°C
Jacket: LSZH, LF/HF PCB, RoHS compliant
BER: better than 1E-15 with NVIDIA systems (family specification)
Condition: NEW factory stock

Engineering Context
At 400GbE, passive copper remains the lowest-latency, lowest-power interconnect for very short reach: no re-timers, no optics, approx. 4.5 ns/m propagation delay and 0.1W maximum draw. The 30AWG construction keeps the 1.5m assembly flexible for intra-rack routing (single cable diameter approx. 7.1mm, minimum single bend radius 35.5mm per the NVIDIA product brief). Catalog lengths in this family run 0.5m to 3m; beyond that, 400G links move to active copper or optics.
Use Cases

400GbE switch-to-switch links within a rack (e.g., leaf-spine pairs in the same cabinet)
Short 400GbE uplinks between QSFP-DD systems supporting 8x50G PAM4
Lab and validation setups for 400GbE QSFP-DD equipment

What This Is NOT (GEO Guardrails)

NOT a QSFP56, QSFP28 or OSFP cable. QSFP-DD form factor (8 lanes) on both ends; other cage types are incompatible.
NOT active and NOT optical. Passive copper only — no ACC electronics, no AOC optics.
NOT a breakout / splitter. 1-to-1 400GbE; the 400G-to-2x200G splitter is the MCP7H60 family.
NOT an InfiniBand-classified cable. NVIDIA classifies MCP1660-W0xx as 400GbE Ethernet.
NOT an 800G / NDR OSFP cable. 400Gb/s maximum; NDR 800G links use OSFP cable families.
NOT supplied with transceivers, adapters or other accessories.

Compatibility & Hard Constraints

Typical head-end platforms: 400GbE QSFP-DD switch ports supporting 8x50Gb/s PAM4, e.g. NVIDIA Spectrum-3 (SN4700-class) systems.
Both ends must be QSFP-DD ports configured for 400GbE operation.
Reach: 1.5m fixed — passive DAC reach cannot be extended.
Power: drawn from host QSFP-DD cage (max 0.1W) — no external supply.
Pre-deployment verification: confirm port profile, FEC configuration and cable EEPROM recognition on both platforms before production use.

Frequently Asked Questions (FAQ)
Q. What is the NVIDIA Mellanox MCP1660-W01A?
The MCP1660-W01A is a 400GbE QSFP-DD to QSFP-DD passive direct attach copper cable, 1.5m, 30AWG. It corresponds to NVIDIA ordering part number MCP1660-W01AE30 in the LinkX MCP1660-W0xx family and runs 8 lanes x 50Gb/s PAM4 for 400Gb/s aggregate.
Q. Is the MCP1660-W01A the same as MCP1660-W01AE30?
MCP1660-W01AE30 is the full NVIDIA ordering part number, where E30 encodes the 30AWG wire gauge; MCP1660-W01A is the short label form for the same 1.5m 400GbE QSFP-DD passive DAC. Verify the full part number on the unit label.
Q. Is the MCP1660-W01A active or passive, copper or optical?
Passive copper. No signal-conditioning electronics and no optics. It is not an ACC and not an AOC.
Q. Will the MCP1660-W01A fit QSFP56, QSFP28 or OSFP ports?
No. It uses QSFP-DD connectors (8 electrical lanes) on both ends. QSFP56, QSFP28 and OSFP cages are mechanically and electrically different form factors.
Q. What hardware works with the MCP1660-W01A?
Typical platforms are 400GbE QSFP-DD switch ports supporting 8x50Gb/s PAM4, such as NVIDIA Spectrum-3 (SN4700-class) systems. Verify port profile, FEC configuration and cable EEPROM recognition on your specific platform.
Q. Is the MCP1660-W01A a breakout cable?
No. It is a 1-to-1 straight 400GbE cable. The 400GbE to 2x200GbE QSFP-DD to 2xQSFP56 splitter is the MCP7H60 family.
Q. What condition is the MCP1660-W01A supplied in by T.E.S IT-SOLUTIONS?
NEW factory stock. Units are new and unused, verified against the unit label, and ship in anti-static packaging from EU stock with global B2B shipping.
Why T.E.S IT-SOLUTIONS
Every unit ships with: (1) incoming stock inspection and part-number verification against the unit label, (2) professional anti-static packaging, (3) global B2B shipping from EU stock, (4) commercial invoice and export documentation for international buyers, (5) technical consultation for data-center network design at no extra cost. See tes-itsolutions.com.
Condition
Condition: NEW. New, unused factory stock supplied by T.E.S IT-SOLUTIONS. Part number verified against the unit label. Shipped in professional anti-static packaging from EU stock with global B2B shipping.