Single Port 25gbe NIC's with 4x PCIe Gen3?

[mattlach]

Hey everyone,

I'm in a bit of a bind, trying to ghetto-mod some extra network capacity into a mini-ITX system and only have a 4x m.2 slot available to me.

I'm considering using a m.2 to 4x PCIe slot riserand creatively mounting it somehow.

Ideally I'd want 25gbe bandwidth out of this solution.

Does anyone know if there are any single slot NIC's that work at full speed on 4x PCIe? Gen 3 or even Gen 4 would do the trick.

I've seen a few dual port ones with 8x slots, but in my experience just running these with half the number of PCIe lanes and only using one port doesnt work well, at least judging by the old Intel AT2 adapters I've tried this on.

Worse comes to worse, I'll just do 10gbe, but I'd really like more bandwidth on this solution.

Appreciate any suggestions!

--Matt

 

[mattlach]

...or does anyone have any experience with any brand of 25Gbit adapter, even dual port ones, working well and attaining full speeds when plugged into an x4 gen3/4 port, despite being an x8 card, if only one of the ports were in use?

Just because my decade old Intel adapters didn't do this, doesn't mean that no new ones will.

 

[chenxiaolong]

I'm doing a similar thing with a dual port Mellanox ConnectX-4 card, although it's with 40Gbps optics and it's an x16 card in an x8 slot. I have no problems maxing out the link with a single port.