Cisco UCS 5108 vs UCS X9508
The UCS 5108 (N20-C6508) is the long-running B-Series blade chassis; its modern Cisco replacement is the UCS X9508 chassis, a 7RU X-Series enclosure with a cable-free midplane, 100G intelligent fabric modules, and X-Fabric for PCIe/GPU resources. For new modular compute, deploy the X9508 with X210c M7 nodes.
Cisco UCS 5108 Chassis
Mature 6RU B-Series blade chassis with a passive midplane and 2 fabric extender bays.
- 6RU; up to 8 half-width or 4 full-width B-Series blades
- 2 I/O bays for IOM/Fabric Extenders (2204/2208/2408)
- Up to 4 power supplies, 8 fans, front-to-back cooling
- Hosts M1-M5 generation blades; nearing end of its product line
Cisco UCS X9508 Chassis
Current 7RU X-Series chassis with a cable-free midplane and 100G intelligent fabric modules.
- 7RU; 8 flexible front slots for compute and future resource nodes
- Intelligent Fabric Modules deliver up to 100 Gbps per node
- X-Fabric Modules add native PCIe Gen4 for GPU/PCIe nodes
- Up to 6 power supplies; Intersight cloud-native management
Cisco UCS 5108 Chassis vs Cisco UCS X9508 Chassis: spec comparison
| Spec | Cisco UCS 5108 Chassis | Cisco UCS X9508 Chassis |
|---|---|---|
| Rack units | 6RU | 7RU |
| Node slots | 8 half-width / 4 full-width | 8 flexible slots |
| Generation hosted | B-Series M1-M5 blades | X-Series M6/M7 nodes |
| Fabric per node | Up to 2x 40G (IOM 2408) | Up to 100 Gbps (IFM) |
| Fabric modules | 2 Fabric Extenders (IOM) | 2 Intelligent Fabric Modules |
| PCIe / GPU fabric | None (no midplane PCIe) | X-Fabric: native PCIe Gen4 to GPU/PCIe nodes |
| Midplane | Passive midplane | Cable-free, midplane-free design |
| Power supplies | Up to 4 | Up to 6 |
| Management | UCS Manager / Intersight | Intersight (cloud-native) |
| Lifecycle status | Legacy / end of product line | Current, actively sold |
Choose Cisco UCS 5108 Chassis if
Keep the 5108 only to continue running an existing B-Series fleet you are not yet ready to migrate; it is not the platform to standardize on for new deployments.
Choose Cisco UCS X9508 Chassis if
Choose the X9508 for any new modular compute standard, especially where you need 100G fabric, future GPU/PCIe resource nodes via X-Fabric, and cloud-native Intersight operations.
Verdict
The 5108 served the B-Series era well but it is a 40G-class, blade-bound chassis at the end of its line. The X9508 is the X-Series successor: a cable-free 7RU enclosure with 100G intelligent fabric, X-Fabric for GPU/PCIe expansion, and Intersight management that decouples compute generations from the chassis. Standardize new builds on the X9508 with X210c M7 nodes.
Frequently asked questions
Can I put X-Series nodes like the X210c M7 in a UCS 5108?
No. X-Series compute nodes require the UCS X9508 chassis and its X-Series fabric. The 5108 only hosts B-Series blades, so adopting X-Series means moving to the X9508 chassis.
What is the main advantage of the X9508 over the 5108?
The X9508 uses a cable-free, midplane-free design with 100G intelligent fabric modules and adds X-Fabric for native PCIe Gen4 to GPU and PCIe resource nodes, so it can evolve across compute generations without forklift changes.
Is the UCS 5108 chassis discontinued?
The 5108 is at the end of its product line as Cisco transitions modular compute to the X-Series. Existing 5108 chassis remain supported per their lifecycle dates, but new modular designs should standardize on the X9508.
Does the X9508 still use UCS Manager?
The X-Series is designed for cloud-native operations through Cisco Intersight. The X9508 is managed via Intersight rather than the on-box UCS Manager model used by the 5108.
More UCS comparisons
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