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- Description
- Specifications
A two-port 10/25 Gb Ethernet adapter in HPE's FlexibleLOM (FLR) form factor, sold as the 640FLR-SFP28. HPE's server QuickSpecs give its full name as the HPE Ethernet 10/25Gb 2-port FLR-SFP28 MCX4121A-ACFT Adapter, naming the Mellanox controller model.
PartSurfer lists the spare part as 840139-001 and links it to HPE 25Gb SFP28 direct attach copper cables (0.5 m, 1 m, 3 m and 5 m) as well as 10GbE SFP+ DAC cables.
The DL380 Gen10 and DL560 Gen10 QuickSpecs list it among the FlexibleLOM choices next to the 817709-B21 (BCM57414) 10/25Gb FLR-SFP28 adapter. The HPE DX560 Gen10 QuickSpecs map the DX-branded 640FLR-SFP28 FIO adapter, P18461-B21, to this standalone part.
HPE's server QuickSpecs point to the separate NIC QuickSpecs for the adapter's technical specifications and limits.
Fit check: the server needs a free FlexibleLOM slot; check that the server's QuickSpecs list 817749-B21, and order SFP28 DACs or optics from HPE's list for 25 Gb links.
HPE's QuickSpecs list this beside the BCM57414 817709-B21; 817721-B21 is another FlexibleLOM in HPE Network Modules, Transceivers and Controllers.
| 817749-B21 Specs | |
| Part number | 817749-B21 (817749B21) |
| Spare part | 840139-001 |
| Name | HPE Ethernet 10/25Gb 2-port 640FLR-SFP28 |
| Controller | Mellanox MCX4121A-ACFT |
| Ports | 2 x SFP28, 10/25 Gb/s |
| Form factor | FlexibleLOM |
| Cables listed by PartSurfer | 25Gb SFP28 DAC 0.5-5 m; 10GbE SFP+ DAC |
| Servers (QuickSpecs) | DL380 Gen10, DL560 Gen10 |
| DX equivalent | P18461-B21 (DX560 Gen10) |
