Dell PowerSwitch SN5600D 800GbE Switch

The Dell PowerSwitch SN5600D is a 2U spine and super-spine switch with 64 OSFP ports of 800GbE plus one 25GbE SFP28 port, built on the NVIDIA Spectrum-4 ASIC, delivering 51.2 Tbps of bidirectional switching capacity, 33.3 Bpps of forwarding and a 160MB fully shared packet buffer, and fed from a 40-60V DC bus bar.

The DC bus bar is the model. Everything else on this switch is shared with the SN5610; the power intake is what makes it a different product, and NVIDIA states plainly that it is what makes the SN5600D "ideal for NVIDIA DGX SuperPOD offerings".

Read the power feed before anything else

There is no AC variant of the SN5600D. The datasheet's power row for this model reads "DC bus bar, input range 40-60 VDC" where the SN5610 and SN5400 columns read "50-60 Hz, 200-240 VAC". A buyer who racks this switch in a conventional AC facility has bought hardware they cannot power.

That constraint is not a defect - it is the point. Rack-scale AI reference architectures distribute DC on a bus bar rather than running a PDU and a power supply per device, because at pod scale the conversion losses and the cable count both become significant. A switch designed to sit in that rack takes its power the same way the compute nodes do. If your facility already has the bus bar, the SN5600D is the correct choice and the SN5610 is the compromise. If it does not, the SN5610 is the correct choice and this switch is unusable.

Everything downstream of that decision - the 1+1 redundancy across two hot-swappable supplies, the four N+1 hot-swappable fans, the reverse-only airflow - follows from the rack design rather than being independently selectable.

Sixty-four 800GbE ports, and one SFP28

Each of the 64 cages is an OSFP running 8 lanes of 100G PAM4, supporting 100, 200, 400 or 800GbE. The reachable densities:

• 64 x 800GbE native OSFP
• 128 x 400GbE
• 256 x 200GbE, and the same figure at 100 and 50GbE
• 128 x 40GbE
• 256 + 1 x 25GbE and 10GbE

Note the +1. The SN5600D has a single SFP28 port where the SN5610 has two. It is a small difference and an easy one to miss when reading across a family datasheet, and it matters if the design assumed a redundant pair for the management plane. Plan for one.

Two hundred and fifty-six ports of 100GbE from 2RU is what makes this switch a chassis replacement rather than a faster aggregation switch. With a radix that large, thousands of hosts fit inside a two-tier fabric, which keeps latency predictable because there is no third tier to traverse.

Spectrum-4, and why the buffer is the specification that matters

Spectrum-4 is NVIDIA's fifth-generation Ethernet switch ASIC. The 160MB packet buffer is monolithic and fully shared across all ports, supporting cut-through traffic from every port simultaneously without compromising scale or feature set.

On an AI fabric that architecture is not a refinement, it is the requirement. Training traffic is synchronised by construction: every node in a collective completes its step at roughly the same instant and transmits at roughly the same instant, so many-to-one incast is the normal operating pattern rather than an occasional event. A buffer partitioned per port exhausts on the ports under pressure while sitting unused elsewhere. A monolithic shared buffer puts all 160MB wherever the burst lands.

Around that sit RoCE with Spectrum-X extensions for AI cloud servers built on Ethernet, end-to-end nanosecond-level timing precision from switch to host, 512,000 forwarding entries dynamically shared across MAC, ARP, IPv4 routes, ACLs, ECMP and VXLAN tunnels, 256-way ECMP, EVPN multi-homing, multi-chassis LAG for active/active Layer 2 multipathing, and hardware-assisted in-service software upgrades. The SN5600D is a Spectrum-X platform switch - pretested and prevalidated with BlueField SuperNIC cards and DPUs, ConnectX SuperNICs and NICs, and LinkX interconnects - which is what the DGX SuperPOD positioning rests on.

Visibility is the Spectrum stack: What Just Happened event-triggered telemetry, hardware-accelerated queue-depth histograms powered by NetQ at sub-microsecond granularity, inband and streaming telemetry, 512,000 on-chip flow counters. Security is a hardware root of trust authenticating BIOS through network operating system, blocking any component or image not signed by NVIDIA.

Physical planning

The chassis is 3.39 in high, 17.20 in wide and 31.00 in deep. The 31-inch depth needs a full-depth cabinet plus rear cabling clearance. Airflow is reverse only. The operating envelope is 0 to 35 C - five degrees tighter than the SN5610, which is worth knowing if the pod runs warm and the two models are being treated as interchangeable.

Non-operating range is -40 to 70 C, relative humidity 5-85%, altitude to 3,050 m. The SN5000 family datasheet publishes no weight, no power draw and no latency figure for any of its three models, so freight, circuit sizing and latency budget all need a physical unit or a Dell quote. No figure is estimated here from the form factor.

Software

NVIDIA Cumulus Linux or Enterprise SONiC Distribution by Dell Technologies, on an ONIE platform that will install alternatives. NVIDIA Air builds a digital twin of the switch and every cable so automation, policy compliance, monitoring, interoperability and upgrade procedures can be validated before the hardware lands. On a secondary-market unit the installed image says nothing about licensing - confirm the intended NOS before purchase.

Where it sits in the range

The SN5610 is the AC-fed equivalent and the default choice outside a bus-bar rack. The SN5400 is the 400GbE member of the family, and the one NVIDIA excludes from Spectrum-X. The SN4700 is the previous Spectrum-3 generation at 32 x 400GbE in 1RU. On the Dell-branded side the Z9864F-ON is the comparable 800GbE PowerSwitch. If the fabric is InfiniBand, the equivalent tier is the Quantum-X800 Q3400-RA - see the Dell AI fabric switch guide. The out-of-band network is Ethernet whichever fabric you choose, and that is the SN2201. The whole set is compared side by side on our 800G AI fabric lineup.

Every unit is professionally reconditioned, fully tested and shipped with warranty. This model is quote-only. Tell us your rack power design, port map, optics plan and quantity and a specialist will come back to you on sourcing and availability.

Specifications