Dell DAC-Q56DD-400G-2.5M Compatible 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable, 2.5m (8ft)

Use the DAC-Q56DD-400G-2.5M compatible assembly where a 400G connection is required between compatible ports. This page covers the 2.5m (8ft) version only, with its own HT part number, specifications and compatibility verification.

OEM Part Number: DAC-Q56DD-400G-2.5MHT Part Number: DAC-Q56DD-400G-2.5M

Product Highlights

• Compatible alternative to Dell DAC-Q56DD-400G-2.5M
• 400G connectivity at 400Gbps
• Interface configuration: QSFP-DD to QSFP-DD
• Fixed length and part number: 2.5m (8ft), DAC-Q56DD-400G-2.5M
• Cable construction: Passive Twinax
• Conductor specification: 26AWG
• Maximum power consumption: 0.1W Per End
• Minimum bend radius: 57mm

The listed modulation format is 8x 50Gbps PAM4. Both host interfaces must be configured for the same aggregate rate and lane arrangement. A connector that fits mechanically does not by itself guarantee that the remote port supports this encoding or breakout mode.

DAC-Q56DD-400G-2.5M occupies the middle of this family between DAC-Q56DD-400G-2M at 2m (7ft) and DAC-Q56DD-400G-3M at 3m (10ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 0.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.

The rated power consumption is 0.1W Per End. Include this load in the host-port power and thermal budget, especially in densely populated switches. Maintain front-panel clearance and do not bundle the cable so tightly that it obstructs airflow around the connectors.

This assembly uses 26AWG conductors, PET jacket, minimum bend radius 57mm. These mechanical characteristics affect how the cable should be dressed behind the equipment. Avoid sharp edges, excessive ties and repeated tight bends close to the connector boots.

The intended application is 400G Ethernet. Listed interface and protocol references include IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0. Confirm that the host firmware and port configuration support the same operating mode.

A passive DAC has no separate optical conversion stage. Its low-power, low-latency operation is useful for short equipment links, but the assembly must remain within the length and signaling mode accepted by both hosts.

The 2.5m (8ft) version is useful when a two-metre run would leave insufficient working slack. Before installation, check the complete horizontal and vertical path so that DAC-Q56DD-400G-2.5M reaches both ports without tension at either connector.

For this Dell application, testing combines digital identification with actual traffic-link verification and electrical continuity, link stability and diagnostic readouts. Both ends are inspected for latch, boot and connector damage. If the project uses a specific hardware revision or a channelized port, send those details so that the intended configuration can be reviewed before shipment.

When ordering, specify DAC-Q56DD-400G-2.5M, cable length 2.5m (8ft) and the host platform. This allows our team to verify both the physical assembly and the compatibility requirement before production. Neutral labeling and customer packing lists can be arranged for volume orders.

HT inspects and tests every completed cable before it enters finished stock. Protective caps or covers are fitted where applicable, followed by anti-static or tray packaging and an outer carton. Custom labels can cross-reference the customer part number, DAC-Q56DD-400G-2.5M and the 2.5m (8ft) length for easier inventory control.

Stock items are generally dispatched within one to three working days after order confirmation. DHL, UPS, FedEx, TNT and EMS are available for international delivery; larger consolidated orders can move by air or sea freight. Customer courier accounts and nominated forwarders are accepted.