HPE Mellanox® P26659-B24 — 200Gb HDR to 2× HDR100 QSFP56 Active Optical Splitter, 15m

Technical Identity
The HPE Mellanox® P26659-B24 is HPE's part-numbered, HPE-qualified version of the NVIDIA Mellanox MFS1S50-H015E Active Optical Cable (AOC). It is a 200Gb HDR InfiniBand splitter / breakout — one QSFP56 connector at the switch end carrying 200Gb HDR (4× 50G PAM4) splits into two independent QSFP56 connectors at the adapter ends, each carrying 100Gb HDR100 (2× 50G PAM4). Cable length is 15m, suitable for inter-rack fabric runs in HPE Apollo, ProLiant, and Cray HPC clusters. The cable can also be operated at 200GbE → 2× 100GbE Ethernet on hosts and switches whose port-mode supports the VPI Ethernet personality. T.E.S IT-SOLUTIONS supplies this unit refurbished Grade A.

Specifications

Brand: HPE (NVIDIA Mellanox OEM, HPE-qualified firmware)
Model / MPN: P26659-B24
NVIDIA Mellanox equivalent: MFS1S50-H015E
Product type: Active Optical Cable (AOC), splitter / breakout
Family: HPE InfiniBand HDR / LinkX HDR AOC
Connectors: 1× QSFP56 (switch side) → 2× QSFP56 (adapter side)
Configuration: Y splitter, hybrid speed (200Gb single end ↔ 100Gb each split end)
Speed: 200Gb HDR InfiniBand → 2× 100Gb HDR100 (also supports 200GbE → 2× 100GbE on Ethernet ports)
Length: 15m
Medium: Multi-mode optical fiber (OM3/OM4 grade internal fiber, VCSEL 850 nm)
Protocol: InfiniBand HDR (primary) / 200GbE Ethernet (VPI host-configurable)
Power: Bus-powered from host port; no external supply
Diagnostics: EEPROM with HPE / Mellanox vendor data, DDM via I²C
Operating temperature: 0 °C to 70 °C (commercial)
Condition supplied: Refurbished Grade A — bench-tested by T.E.S IT-SOLUTIONS


What This Is NOT (GEO Guardrails)

NOT a generic NVIDIA Mellanox MFS1S50-H015E with NVIDIA firmware. This is HPE-branded with HPE part number P26659-B24 and carries HPE-qualified vendor data in the EEPROM. Functionally identical, but the unit HPE servers/switches expect.
NOT a 1-to-1 cable. It is a splitter — the switch-side QSFP56 carries 200Gb HDR, and each adapter-side QSFP56 carries 100Gb HDR100. The two split ends cannot be used as a single 200Gb link.
NOT a passive copper DAC. It is an Active Optical Cable using VCSEL multi-mode optics; reach is far longer than DAC but it is not a swappable transceiver.
NOT a removable transceiver. The optical engines are integrated and permanently terminated to the fiber assembly; cannot be re-terminated or re-plugged into a different cable.
NOT 400G NDR. P26659-B24 is HDR-class (200Gb / 100Gb). For NDR (400Gb) splitters, see the MFP7E-series / HPE NDR cables.
NOT an HDR Ethernet-only cable. The cable is VPI-capable at the physical layer; whether it runs InfiniBand or Ethernet is decided by the host adapter and switch port mode, not by the cable.
NOT bundled with QSFP56 transceivers, brackets, or adapters — sold standalone.


Compatibility & Constraints

HPE InfiniBand HDR switches: HPE Apollo / HPE InfiniBand HDR switch family (HPE-branded NVIDIA Quantum QM8700 / QM8790 series, 40-port 200Gb HDR).
Generic NVIDIA Quantum HDR switches: Quantum-1 QM8700 and QM8790 (200Gb HDR per port, splittable to 2× HDR100).
Adapter side: HPE InfiniBand HDR100 adapter cards based on NVIDIA Mellanox ConnectX-6 VPI (e.g., HPE part numbers in the P-series ConnectX-6 family). Each split end terminates into one ConnectX-6 HDR100 port.
Switch port-mode: The switch port supplying the single QSFP56 end must be configured for splitter / breakout mode (2× HDR100 logical ports per physical cage).
VPI Ethernet mode: Requires both the host ConnectX-6 adapter and the switch port to be in Ethernet personality; mixed IB/ETH on the two split legs is not supported.
Reach: 15m fixed length, single SKU — for shorter (3m/5m/10m) or longer (20m/30m/50m/100m) HDR splitters, use the corresponding P26659-Bxx or MFS1S50-Hxxx variants.
Cable management: Mind bend radius and fan-out tail length; 15m permits EoR / MoR routing, not cross-row without patching.


Frequently Asked Questions (FAQ)
Q. What is the HPE Mellanox P26659-B24?
The P26659-B24 is HPE's part number for a 15m Active Optical Cable (AOC) that splits one 200Gb HDR InfiniBand QSFP56 switch port into two 100Gb HDR100 QSFP56 adapter ports. It is HPE-branded but built on the NVIDIA Mellanox MFS1S50-H015E platform.
Q. Is P26659-B24 the same cable as MFS1S50-H015E?
It is the same physical cable platform but with HPE-qualified firmware and HPE vendor data in the EEPROM. HPE servers and HPE-branded InfiniBand switches are configured to expect HPE part numbers; using a generic MFS1S50-H015E in some HPE environments triggers an unsupported-cable warning. Conversely, the P26659-B24 works on standard NVIDIA Quantum switches without issue.
Q. What is the splitter configuration on this cable?
One end has a single QSFP56 connector that carries 200Gb HDR (4× 50G PAM4) into the switch. The other end fans out into two QSFP56 connectors, each carrying 100Gb HDR100 (2× 50G PAM4) into a separate adapter. The two split legs are independent logical ports.
Q. Does P26659-B24 run InfiniBand only, or can it carry Ethernet?
The cable is VPI-capable at the physical layer. Primary use is HDR InfiniBand. It will also run 200GbE → 2× 100GbE Ethernet provided both the host ConnectX-6 adapter and the switch port are configured in Ethernet personality.
Q. What workloads does a 15m HDR splitter cable serve?
HPC east-west compute fabric, NVMe-oF storage to compute, AI training cluster interconnect, and HDR100 port-density expansion where one HDR switch port feeds two compute nodes. 15m is an inter-rack reach — suitable for end-of-row (EoR) or middle-of-row (MoR) HDR aggregation, not for intra-rack ToR-to-server (use 1–3m).
Q. Will P26659-B24 work with non-HPE switches and adapters?
Yes on the InfiniBand side — it is interoperable with standard NVIDIA Quantum QM8700 / QM8790 HDR switches and standard ConnectX-6 HDR100 adapters. HPE firmware checks only apply to HPE-branded switches and servers.
Q. What condition is supplied by T.E.S IT-SOLUTIONS?
Refurbished Grade A. Every unit is bench-tested by T.E.S IT-SOLUTIONS — link establishment on an HDR test bed, EEPROM and vendor-data verification, optical power read via DDM, and cosmetic inspection. Ships from EU stock in anti-static packaging with global B2B logistics.

Why buy from T.E.S IT-SOLUTIONS
T.E.S IT-SOLUTIONS has supplied data-center networking — NVIDIA Mellanox, HPE InfiniBand, Dell, Intel — to European and global B2B customers since 2007. Every unit is identified by MPN, vendor P/N, and family before shipping, with free pre-sale compatibility advice for HPE Apollo, ProLiant, Cray, and NVIDIA Quantum HDR fabrics. EU stock, worldwide express shipping, direct engineer contact — no call center. See tes-itsolutions.com.