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# 400G QSFP112 Passive Cable 0.5m for DGX Spark Stacking

**Type:** Product page · **SKU:** CE11264 · **Brand:** [Core Electronics](https://core-electronics.com.au/brands/core-electronics-australia)
**Page:** https://core-electronics.com.au/400g-qsfp112-passive-cable-0-5m-for-dgx-spark-stacking.html ([markdown](https://core-electronics.com.au/400g-qsfp112-passive-cable-0-5m-for-dgx-spark-stacking.html.md))

Turns two DGX Spark systems into a two-node cluster over a short, low-power copper link between their ConnectX-7 ports.

## Pricing

- **Price:** $234.42 (inc GST) — $213.11 AUD, exc GST

## Availability & dispatch

- Available with a lead time — expect dispatch between Nov 10 and Nov 17.

## How to buy

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## Description

A 0.5 m passive direct attach copper (DAC) cable with a QSFP112 connector on each end, for linking two [NVIDIA DGX Spark](https://core-electronics.com.au/nvidia-blackwell-spark.html) systems directly to each other.

Each DGX Spark has two ConnectX-7 QSFP ports on the back, and clustering two units starts with a physical cable between them. This cable runs from one port on each Spark to the other with no switch in between. You then configure the network using NVIDIA's Connect Two Sparks playbook.

The cable is rated for 400G, but the speed between two Sparks is set by their ports: up to 200 Gb/s per link. Because it is passive copper, latency stays at the nanosecond level.

The 0.5 m length suits Sparks placed side by side or stacked. The cable cannot be used in OSFP ports, which use a different form factor. To unplug it, pull the tab to release the latch.

### Features

- Supports distributed AI training and RoCE networking between two machines through a direct NIC-to-NIC connection between QSFP112 adapters
- Draws under 0.25 W because it is a passive assembly with no active components in the signal path
- Plugs in and unplugs with both systems running, because it is hot-pluggable to the QSFP112 MSA
- Identifies itself to the host port through an onboard I²C EEPROM on the SFF-8636 management interface
- Carries 100 Gb/s per lane over solid silver-plated copper conductors, a foam-skin PE dielectric and gold-plated contact pads

### Specifications

| 400G QSFP112 Passive DAC Cable 0.5 m |
|---|
| Property | Value |
| Cable type | Passive direct attach copper (DAC), twinax |
| Connectors | QSFP112 to QSFP112 |
| Length | 0.5 m |
| Wire gauge | 30 AWG |
| Rated data rate | 400G (4 × 100G PAM4; 4 transmit and 4 receive channels) |
| Link rate on DGX Spark | Up to 200 Gb/s per port |
| Power consumption | Under 0.25 W |
| Supply voltage | 3.3 V |
| Differential impedance | 100 Ω (90–110 Ω) |
| Management interface | SFF-8636, I²C EEPROM |
| Standards | QSFP112 MSA Rev 2.1, IEEE 802.3ck |
| Conductors | Solid copper, silver-plated |
| Jacket | PVC, UL listed CM 75 °C |
| Latch | Pull-to-release |
| Operating case temperature | 0 to 70 °C |
| Storage temperature | −40 to 85 °C |
| Operating humidity | 5–85 % non-condensing |
| Compliance | FCC Class B, EN55022 Class B, RoHS (EU) 2015/863, REACH |
| Warranty | 3 years |

### Resources

- [Datasheet](https://resource.naddod.com/files/2026-08-12/q112-400g-dac-datasheet-017676.pdf)
- [DGX Spark User Guide: Clustering](https://docs.nvidia.com/dgx/dgx-spark/spark-clustering.html)
- [NVIDIA Connect Two Sparks playbook](https://build.nvidia.com/spark/connect-two-sparks)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/C/E/CE11264_ecommerce_1793313437632.jpg)