NVIDIA Mellanox® MSB7520-E — Switch-IB EDR InfiniBand Spine Blade (36-Port, 100 Gb/s)

Technical Identity
The NVIDIA Mellanox® MSB7520-E is a Switch-IB™ EDR InfiniBand spine / line blade providing 36 × 100 Gb/s EDR ports via QSFP28 cages. It is a hot-swappable module designed for NVIDIA Mellanox director-class chassis (CS7500-series), delivering non-blocking, full-bisection fabric capacity for HPC, parallel storage, and InfiniBand-attached compute clusters. Built on the Switch-IB ASIC, it provides 7.2 Tb/s of aggregate switching throughput per blade with sub-90 ns port-to-port latency, adaptive routing, and hardware-based congestion control.

Specifications

OEM: NVIDIA Mellanox
Part Number (MPN): MSB7520-E
Product type: Spine / line blade for InfiniBand director chassis
ASIC family: Switch-IB™ (EDR-class InfiniBand silicon, SwitchX-2 successor)
Protocol: InfiniBand only (no Ethernet / no VPI mode)
InfiniBand generation: EDR — 100 Gb/s per port (4 × 25 Gb/s NRZ lanes)
Port count: 36 × QSFP28
Aggregate throughput: 7.2 Tb/s, non-blocking
Port-to-port latency: ≤ 90 ns
Forwarding: cut-through, adaptive routing, hardware congestion control
Form factor: hot-swappable blade module for CS7500-series director chassis
Management: chassis-level via MLNX-OS / NVIDIA Onyx; subnet manager runs on chassis supervisor or external UFM / OpenSM
Power & cooling: drawn from parent chassis PSUs and fan trays — no on-blade PSU
Condition: New, factory-sealed


What This Is NOT

NOT a standalone 1U / 2U switch. This is a blade module that installs only into NVIDIA Mellanox CS7500-series director chassis — it will not operate outside its parent chassis.
NOT an Ethernet switch. Switch-IB is an InfiniBand-only ASIC. It does not run Ethernet (no Spectrum capability, no Ethernet-only RoCE mode).
NOT compatible with HDR (200 Gb/s) or NDR (400 Gb/s) fabrics at line rate. EDR silicon — ports run at 100 Gb/s, auto-negotiating down to FDR / QDR with appropriate cables.
NOT a Quantum-series module. Quantum-1 (HDR) and Quantum-2 (NDR) blades are not interchangeable with Switch-IB EDR blades.
NOT bundled with QSFP28 transceivers, AOC / DAC cables, rail kits, or chassis components — sold as the blade module only.


Compatibility & Constraints

Parent chassis: NVIDIA Mellanox CS7500-series InfiniBand director switches (CS7500 648-port, CS7510 324-port, CS7520 216-port). Verify chassis revision and firmware before insertion.
Host adapters: NVIDIA Mellanox ConnectX-4 / ConnectX-4 Lx EDR-capable variants and ConnectX-5 EDR HCAs (MCX4xx / MCX5xx EDR SKUs). ConnectX-6 / ConnectX-7 adapters down-negotiate to EDR.
Cabling: EDR QSFP28 passive DAC (MCP1600-Exxx), EDR QSFP28 AOC (MFA1A00-Exxx), or EDR QSFP28 optical transceivers (MMA1B00-E100 SR4, MMS1C00-E100 LR4). FDR-grade QSFP+ links auto-negotiate down to 56 Gb/s FDR.
Subnet management: chassis-level subnet manager (built-in MLNX-OS SM, NVIDIA UFM Enterprise, or external OpenSM). The blade is managed by the CS75xx supervisor module.
Firmware: Switch-IB EDR firmware must match the chassis system image; mixed FW revisions can prevent blade enumeration.
Deployment: spine in CLOS / fat-tree topologies, leaf in dragonfly, HPC / AI training fabric, parallel file system (Lustre, GPFS, BeeGFS) interconnect, NVMe-oF storage backbone.


Frequently Asked Questions (FAQ)
Q. What is the NVIDIA Mellanox MSB7520-E?
It is a 36-port EDR InfiniBand spine / line blade for the NVIDIA Mellanox CS7500-series director-class switch chassis, based on the Switch-IB™ ASIC, delivering 100 Gb/s per QSFP28 port with 7.2 Tb/s non-blocking switching capacity.
Q. Can the MSB7520-E run in Ethernet mode?
No. The Switch-IB ASIC is InfiniBand-only — there is no Ethernet, standalone RoCE, or VPI mode. For Ethernet at 100 GbE use a Spectrum-family switch such as SN2700, SN2410, or SN3700.
Q. Will this blade work in a standalone 1U switch chassis?
No. The MSB7520-E is a blade designed exclusively for NVIDIA Mellanox CS7500-series director chassis (CS7500 / CS7510 / CS7520). It will not boot or pass traffic outside its parent chassis.
Q. What cables and transceivers should I pair with it?
QSFP28 EDR passive DAC (MCP1600-E0xx series), QSFP28 EDR AOC (MFA1A00-Exxx series), or QSFP28 EDR optical transceivers (MMA1B00-E100 SR4, MMS1C00-E100 LR4). FDR-grade QSFP+ links auto-negotiate down to 56 Gb/s FDR.
Q. Is this a new or refurbished unit?
New, factory-sealed unit from T.E.S IT-SOLUTIONS EU stock. Original NVIDIA Mellanox packaging where supplied. Ships worldwide with professional anti-static packaging and B2B invoicing.

Why buy from T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS is a Europe-based NVIDIA Mellanox specialist serving HPC, AI, and enterprise data-center procurement teams since 2007. Every InfiniBand component is identified by MPN, NVIDIA P/N, ASIC family, and chassis compatibility before it ships, and every customer receives free pre-sale design consultation for director-class fabric topologies (spine / leaf, fat-tree, dragonfly). Multi-currency B2B invoicing, EU stock with worldwide express options, and direct engineering contact — not a call-center.