Cisco Nexus 9164E-NS4-O (Spectrum-X)
64 × 800G in 2U. That is 51.2 Tb/s of switching through 64 OSFP cages.
- Logical ports64 × 800G
- Physical cages64 × OSFP
- Switching capacity51.2 Tb/s
- Rack units2U
- Typical power2,000 W
- Maximum power2,900 W
- Fabricethernet
- ASICNVIDIA Spectrum-4
Breakout
A port faster than the endpoint it serves can be broken out when the speeds divide cleanly. That raises the usable port count. Two-tier capacity goes as the square of the port count, so it moves the tier boundary a long way.
| Endpoint speed | Breakout | Usable ports |
|---|---|---|
| 800G | none | 64 |
| 400G | 2:1 | 128 |
| 200G | 4:1 | 256 |
| 100G | 8:1 | 512 |
Roles and optics
- Suitable for: compute, storage fabrics
- Cage type: OSFP. A module of any other form factor will not seat
- Accepted optic coding: nvidia, cisco, universal
- Management: Internally managed
- Part number:
N9164E-NS4-O
Coding matters more than it looks. A switch may refuse a transceiver that is not coded for it, and that is one of six axes that have to agree before a link comes up. The others are form factor, reach, fibre type, fibre connector and ferrule polish. See optics compatibility.
Notes
Nexus 9100 series. Verified: 2RU, 64x800G OSFP, 51.2 Tb/s, NVIDIA Spectrum-4 ASIC, 160 MB on-die buffer, with 2x400G / 4x200G / 4x100G breakout per port. Being Spectrum silicon it supports the Spectrum-X adaptive routing and congestion control path when paired with NVIDIA SuperNICs, and is covered by the Cisco NVIDIA Cloud Partner-compliant reference architecture. Power draw is unverified — the data sheet quotes a 3000 W supply rating, which is capacity rather than consumption. Serving 400G endpoints is handled by automatic 2:1 breakout, giving 128 usable ports.
Source: Cisco N9164E-NS4-O data sheet, verified 2026-08. Ports, rack units, and ASIC confirmed; power figures are NOT (only the 3000 W HVAC/HVDC supply rating is given). Needs verification 2026-08-06