NVIDIA/Mellanox QDD-400G-2QAC Compatible 400G QSFP-DD 8 x 50G PAM4 to 2 x 200G QSFP56 4 x 50G PAM4 Ethernet Active Copper Breakout Cable

The QDD-400G-2QAC compatible series is designed for NVIDIA/Mellanox hosts requiring a 400G ACC connection. Its QSFP-DD to 2x QSFP56 arrangement is supplied as an active copper assembly with the cable and signal-conditioning interfaces supplied together. Use the specifications to assess the physical assembly, then follow the exact length and part-number links when preparing a bill of materials or requesting a compatibility check.
Series Part Number: QDD-400G-2QACHT Part Number: QDD-400G-2QAC
Product Highlights
- HT-manufactured compatible alternative for NVIDIA/Mellanox QDD-400G-2QAC
- 400G aggregate connectivity at 400Gbps
- Interface configuration: QSFP-DD to 2x QSFP56
- Active
- Length configurations covered: 5m (16ft)
- Conductor specification: 28AWG
- Power consumption: 1.45W(QSFP-DD End) 0.62W(QSFP56 Per End)
- Operating temperature: 0 to 70°C (32 to 158°F)
Available Lengths and Corresponding Part Numbers
The documented series configuration is 5m (16ft). Use the relevant OEM reference below together with the HT identity and required length when requesting a quotation. If another length carries a different OEM part number, it must be reviewed and ordered as that distinct configuration.
Compatible OEM Part Numbers
- QDD-400G-2QAC05
Specifications
| HT Part Number | QDD-400G-2QAC |
|---|---|
| Manufacturer | HT |
| Form Factor | QSFP-DD to 2x QSFP56 |
| Max. Data Rate | 400Gbps |
| Cable Length Options Covered | 5m (16ft) |
| Wire AWG | 28AWG |
| Minimum Bend Radius | 80mm |
| Max. Power Consumption | 1.45W(QSFP-DD End) 0.62W(QSFP56 Per End) |
| Cable Type | Active |
| Jacket Material | PVC |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Protocols | QSFP-DD MSA, SFF-8636, SFF-8679 |
Field Installation and Maintenance
Inspect the route and both connectors before installation, then support the cable without pulling on either connector housing. During maintenance, release the latch properly rather than using the cable as a handle. Keep protection on unused ends, and if the assembly is removed for later use, coil it loosely and record its part number so the same length can be returned to service. For this series, keep the interface rate, ACC construction and length-specific OEM reference together throughout that review.
Applications and Deployment
An ACC link combines copper cabling with active electronics at the connector ends. It avoids separate patch leads but is not interchangeable with a passive DAC merely because the cages look alike. Confirm the supported cable type, lane mode and power allowance on every attached port. For this series, the listed interface is QSFP-DD to 2x QSFP56 and the aggregate rate is 400G.
Cable Construction and Routing
The specification table records the conductor specification is 28AWG; the jacket material is PVC; the minimum bend radius is 80mm; the operating temperature is 0 to 70°C (32 to 158°F); the power consumption is 1.45W(QSFP-DD End) 0.62W(QSFP56 Per End). Use those values when preparing the rack pathway and receiving checklist. Do not pull a connector by its cable, compress the run under tight ties or force excess length into a sharp coil. Connector protection should remain in place until the assembly is ready for insertion.
Quality Assurance and Packaging
The cable and both connectors are inspected before a functional link test. Connector protection and bend-safe packing reduce handling damage during transport and storage. Customer or site labels can be added for field inventories, with different lengths separated to simplify issue and return of spare assemblies. Both connector ends are inspected as part of the complete assembly, and protective packing is selected to avoid tight bends during transport and storage.
NVIDIA/Mellanox Compatibility and Factory Testing
A field-ready cable needs both correct identification and a stable operating link. Our pre-packing check therefore includes the connectors, host recognition and link behavior. For equipment with uncertain revision history, providing the host model and software release helps identify compatibility requirements before the assembly reaches the installation site. Series-level inspection is followed by the exact length and OEM configuration selected for dispatch. Functional verification includes link establishment and diagnostic indications where the host exposes them.
Ordering Information
Request the cable by its exact part number and length, and state the equipment model if compatibility confirmation is needed. Site orders can list quantities by rack or installation team. Any requested label should retain the part number so a removed or spare cable can still be identified accurately. For this series, follow the corresponding length link, quote that exact OEM part number and keep different lengths on separate order lines. HT part number QDD-400G-2QAC identifies the product family; the linked page provides the final length-specific identity.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, with production lead times confirmed for larger quantities. International courier, air freight and sea freight are available; customer courier accounts and nominated forwarders are accepted.
Frequently Asked Questions
Is this an original NVIDIA/Mellanox cable?
No. It is an HT-manufactured compatible cable for equipment that specifies QDD-400G-2QAC, not an original NVIDIA/Mellanox-branded product.
Are different lengths and OEM part numbers separate products?
Yes. Where a length has its own OEM reference, follow the corresponding link above and order that exact part number on its own line. Do not substitute another length only because the connector arrangement is the same.
Does this ACC cable require separate modules at each end?
No. The connector ends and cable form one complete direct-attach assembly. The ends are not detachable standalone transceivers, and the complete product is tested together.
What information helps confirm compatibility?
Provide the equipment manufacturer and model, port type, hardware revision and software release, together with the required OEM reference, length and quantity. Breakout projects should also identify the intended lane configuration.
