‌MCIO 124 Pin to 2 X MCIO 74 Pin -700mm

‌MCIO 124-Pin to 2 × MCIO 74-Pin High-Speed Data Cable – 700 mm

Technical Description & Engineering Overview (700 mm Length)

1. Product Summary

The MCIO 124-Pin to dual MCIO 74-Pin 700 mm cable is a high-speed PCIe/NVMe interconnect harness designed for splitting a single 124-pin MCIO host interface into two independent MCIO x8 (38-pair) 74-pin downstream ports. It is used in modern PCIe Gen4/Gen5 server, storage, and accelerator backplane architectures where high-density, low-loss, and low-crosstalk routing is required.

2. Electrical & Signaling Characteristics

High-Speed Capabilities

Supports PCIe Gen4 (16 GT/s) and PCIe Gen5 (32 GT/s) signaling when used in compliant system designs.

Extremely low insertion loss and controlled impedance across a 700 mm run through the use of tuned twin-ax differential pairs.

Differential Pair Structure

Each 74-pin MCIO segment carries:

8 × PCIe lanes (x8)

Differential pairs individually shielded or foil-wrapped depending on build

Skew-matched to within tight tolerances for high-speed retimer/redriver applications

Impedance Control

Nominal differential impedance: 85 Ω ± 10%

Pair-to-pair skew: < 5 ps (typical)

Crosstalk minimized through pair isolation and optimized routing geometry

Cable Grade

30–32 AWG ultra-low-skew twinax, typically with:

Silver-plated copper conductors

High-temperature FEP/PE dielectric

Foil + braid shielding depending on spec

Optimized for long-reach 700 mm PCIe Gen4/Gen5 performance in server chassis.

3. Mechanical Design

Connector Interfaces

Host Side:

MCIO 124-Pin (4C/4× x8 lanes)

High-density, friction-latch or screw-latch depending on system

Device Side (Dual Outputs):

2 × MCIO 74-Pin connectors

Each delivers a full PCIe x8 link (or can be bifurcated as subsystem configuration requires)

Pin-Out Consistency

1:1 lane mapping from MCIO 124-pin to each MCIO 74-pin output

Maintains RX/TX polarity, reference clock routes, sideband signals (PERST#, CLKREQ#, SMBus, etc.)