Abstract

In March 2025 Tolly Enterprises assessed the Dell PowerSwitch Z9864F-ON, a 64-port 800 GbE aggregation switch aimed at AI/ML fabrics and other high-density data-center cores. Engineers measured Layer-2 throughput, latency and energy efficiency using an RFC 2544 test suite driven by Keysight AresONE 800 GbE traffic generators, with every port active in a bidirectional “snake” topology.

Performance proved strictly line-rate. With all 64 × 800 GbE interfaces forwarding simultaneously, the switch sustained its full 51.2 Tb/s capacity at every frame size of 512 bytes and larger; even 256-byte frames reached 90.9% of line rate, while 64-byte frames still delivered 14.1 Tb/s (27.6 %).

Latency tests using a port-to-port setup recorded store-and-forward delays of 1.03–1.07 µs and cut-through delays as low as 755 ns, ensuring microsecond-class responsiveness. Power analysis yielded an ATIS-weighted draw of 1,064 W, translating to 48.1 Gb/s per watt (TEER) for the fully loaded chassis—competitive for an 800 GbE fabric switch operating at maximum bandwidth.