Dell PowerEdge XE9640
4 × H100 SXM per node, with 4 compute rails at 400G. That is 1.6 Tb/s of scale-out network per node.
- GPUs per node4 × H100 SXM
- Compute rails4 × 400G
- Scale-out bandwidth1.6 Tb/s
- Storage links1 × 200G
- In-band links1 × 100G
- BMC ports1
- Rack units2U
- Typical power5.5 kW
- Maximum power6 kW
What this means for the fabric
4 compute NICs means 4 rails. In a rail-optimized design each of those rails is sized on its own against the node count, then multiplied back up, so the leaf tier is driven by the rail count and not by the total endpoint count.
Storage and in-band management are separate fabrics with their own switches and their own optics, and the 1 BMC port per node feed the out-of-band network, which also has to carry every switch and every PDU in the cluster.
Power and racks
At 5.5 kW typical draw, this node fills a rack's power budget long before it fills the space. A 45 kW rack takes 8 of them on power alone, against 21 on rack units. Power is what actually sets the rack count.
Notes
Dense 2U liquid-cooled 4-GPU node. Halving rails halves the leaf switch count for a given node count, but doubles the nodes needed for a given GPU target.
Source: Dell PowerEdge XE9640 documentation, verified 2026-08. Power is approximate. Needs verification 2026-08-06