DAC cables for mellanox https ConnectX MCX4121A-XCAT

kevin wilson

New Member
Apr 4, 2015
Hi all,

I have bought two dual port mellanox nics, as in the following link:

Mellanox MCX4121A-XCAT ConnectX-4 Lx EN Network Interface Card 10GbE Dual-Port SFP28 PCIe3.0 x8 ROHS R6

Each of these nics is installed on a different host.
I want to buy a DAC cable of 2 meter length, for connecting these hosts.
Can I get please links for where can I buy such cables which are known *for sure* to work with the nics ?
I heard that mellanox manufactures cables but they are a bit expensive.
Also I saw in several amazon links where buyers complained that the cable they bought did not work, so i prefer not to take a risk and get recommendation from people who actually have tried it and
it worked.




New Member
Nov 24, 2018
DAC pricing varies wildly based on capability, ie you don’t need a 100GbE capable cable for your 10GbE NICs. My go to is to use the OEM reference table so I know what the supported OEM versions are, you can often find these at decent pricing on eBay...but good luck finding them without a part number. There are other options like fs.com that claim full compatibility, but I can’t speak to that as eBay has always worked out for me.