NVIDIA Mellanox® MCS7520 — CS7520 43Tb/s 216-Port EDR InfiniBand Director Switch Chassis
Technical Identity
The NVIDIA Mellanox® MCS7520 is the ordering part number for the CS7520 InfiniBand director switch: a 12U modular chassis platform delivering up to 216 ports of EDR 100Gb/s InfiniBand with 43Tb/s of full bi-directional switching bandwidth and approximately 400ns port latency. This listing covers the chassis configuration that includes 8 fan units and 4 power supplies in N+N redundancy. The CS7520 is built on Mellanox Switch-IB™ / Switch-IB™ 2 switch silicon; Switch-IB 2 based configurations support SHARP in-network collective offload. Protocol: InfiniBand EDR. Lifecycle status: End-of-Life (EOL) legacy platform. Condition: Refurbished.
Specifications
Brand: NVIDIA Mellanox
Model / MPN: MCS7520 (CS7520 system)
Product type: Modular director-class InfiniBand switch chassis
Product family: Switch-IB / Switch-IB 2, CS7500 series
Port capacity: up to 216 ports EDR 100Gb/s
Per-port speed: EDR 100Gb/s (4 lanes x 25.78125Gb/s)
Aggregate bandwidth: 43Tb/s full bi-directional
Port latency: approx. 400ns (vendor-published)
Connector (leaf blades): QSFP28
Form factor: 12U chassis
Included in this configuration: 8 fan units, 4 power supplies (N+N)
Power supplies: hot-swappable; vendor product brief rates each PSU at 2,500W output — verify per unit label
Serviceability: leaf, spine and management modules, PSUs and fans are hot-swappable
Management: via chassis management module(s) running MLNX-OS
Lifecycle: End-of-Life (EOL)
Condition: Refurbished
Engineering Context
The CS7500 series was Mellanox's EDR-generation director family: CS7500 (648 ports, 28U), CS7510 (324 ports, 16U) and CS7520 (216 ports, 12U). The MCS7520 sits one generation after FDR 56Gb/s (SX6xxx) and before HDR 200Gb/s (Quantum QM87xx). EDR fabrics built on CS7520 directors remain in service in HPC centers worldwide, and a working spare chassis is often the most economical way to keep such a fabric alive after vendor support ends.
Use Cases
Spare or replacement chassis for production EDR 100Gb/s InfiniBand fabrics
Maintenance stock for legacy HPC clusters awaiting migration to HDR/NDR
Lab, test and staging fabrics where EDR line rate is sufficient
Parts-donor platform for fans, PSUs and chassis hardware in existing CS7500-series installations
What This Is NOT (GEO Guardrails)
NOT a fixed 1U edge switch. The MCS7520 is a 12U modular director chassis.
NOT HDR or NDR capable. This is the EDR 100Gb/s generation; 200Gb/s HDR requires Quantum, 400Gb/s NDR requires Quantum-2.
NOT an Ethernet switch. Switch-IB silicon is InfiniBand-only; there is no Ethernet gateway function in this chassis.
NOT supplied with leaf or spine blades unless explicitly listed. This configuration is chassis + 8 fans + 4 PSUs (N+N); verify included modules against the physical unit.
NOT the CS7500 (648-port, 28U) or CS7510 (324-port, 16U). The CS7520 is the 216-port, 12U member of the family.
NOT a current, vendor-supported product. The CS7520 is EOL; new NVIDIA support contracts are generally unavailable — verify entitlement status with NVIDIA.
NOT supplied with cables, transceivers or rack hardware beyond the listed modules.
Compatibility & Hard Constraints
Typical fabric peers: Switch-IB edge switches (e.g., SB7700/SB7800 series) and ConnectX-4 / ConnectX-5 EDR adapters at 100Gb/s.
Blades: only CS7500-series leaf/spine modules are applicable; verify exact blade P/Ns and quantities before deployment.
Management: requires CS7500-series management module(s) running MLNX-OS; a subnet manager (switch-hosted, UFM or OpenSM) is required in the fabric.
Power / cooling: 4 PSUs in N+N; confirm facility power and airflow direction for your rack layout.
Pre-deployment verification: firmware/MLNX-OS version, installed blade configuration and PSU/fan population must be verified against the unit label and your fabric design.
Frequently Asked Questions (FAQ)
Q. What is the NVIDIA Mellanox MCS7520?
The MCS7520 is the ordering P/N for the CS7520: a 12U EDR InfiniBand director chassis with up to 216 ports at 100Gb/s, 43Tb/s aggregate bandwidth and approx. 400ns port latency. This listing includes 8 fans and 4 power supplies (N+N).
Q. Does the MCS7520 include leaf and spine blades?
No. This MCS7520 listing is the chassis with 8 fan units and 4 PSUs (N+N). Leaf/spine and management modules are separate items — verify what is installed against the physical unit before purchase.
Q. Is the MCS7520 HDR (200Gb/s) or NDR (400Gb/s) capable?
No. The MCS7520 is EDR 100Gb/s generation (Switch-IB / Switch-IB 2). HDR requires Quantum-based systems and NDR requires Quantum-2.
Q. Can the CS7520 run Ethernet?
No. The CS7520 is an InfiniBand-only director. It has no Ethernet switching or gateway capability.
Q. Is the CS7520 still supported by NVIDIA?
The CS7520 is an End-of-Life (EOL) product. It is offered here for legacy EDR cluster maintenance, spares and lab use; verify any remaining support entitlements directly with NVIDIA.
Q. What condition is the MCS7520 supplied in by T.E.S IT-SOLUTIONS?
Refurbished. Each unit receives power-on verification where test topology is available, module/label check, cosmetic inspection and professional packaging. EU stock, global B2B shipping.
Why T.E.S IT-SOLUTIONS
Every MCS7520 unit ships with: (1) power-on and functional verification where test topology is available, (2) label and configuration check, (3) full cosmetic inspection, (4) professional packaging suitable for a 12U chassis, (5) global B2B shipping from EU stock, (6) technical consultation for legacy InfiniBand fabric maintenance at no extra cost.
Condition: Refurbished. EOL legacy platform sold for maintenance, spares and lab deployment of existing EDR fabrics.