← All network cards

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BrandMellanox
ModelConnectX-4 Lx EN MCX4121A-ACAT
Part numberMCX4121A-ACAT
TypeNetwork card
ConnectorSFP28
InterfacePCIe 3.0 x8
Ports2 x 25GbE
Listed for27 NAS models

Manufacturer notes: DSM version requirement: 6.2-23739 or later version. (Only applicable to models with DSM.); For better performance, we strongly recommend installing the network interface card into the PCIe 3.0 x8 (white) slot first. (Only applicable to RS3617xs, RS3614xs+, RS3614xs, and RS3614RPxs)

Compatible NAS models

Synology (27)

Source: Synology's official compatibility list. Always check the slot, bracket, OS version and installation notes for your NAS before buying.