The Supermicro X10DRi-T4+ mainboard has a 10gig nic - copper (RJ45 ports), so it runs hot. Temperatures are usually around 70 degrees C for the first and slightly less for the second one. I'm looking for ways to keep the nic cool. Why is it so hot anyway, given that it's only connected with a 1Gbps link?
This is a home lab server in a soho environment where the usual jet engine stock fans are not an option, so I made it quiet by replacing all fans, installed Noctua NH-D9DX i4 cpu fans and sq power supplies. For the most part, this works well, cpu temperatures are between 30 and 40 degrees C, so are the hdds, some ram modules are above 40 degrees C. The only hot spot is the 10g nic which is constantly around 70 degrees C. It's in the top left corner if you look at this picture, there's no place to mount a rear fan.

As you can see, the heatsink is where the PCIe slots are, so it's right under the SAS card, an LSI 9201-16i. The drives connected to that card are rarely under high load, often idle, it used to be in the same place on an older but similar mainboard, but now it's right above the heatsink of that 10g nic. I'm looking for ideas on how to improve this situation in that corner.
I should note that the onboard nic is not used for 10G networking. If I wanted 10G networking, I would use SFP cards, which I already do elsewhere, those do not get hot at all. Unfortunately, when I picked the mainboard, I didn't notice that it has copper 10G networking onboard.
Any ideas?
This is a home lab server in a soho environment where the usual jet engine stock fans are not an option, so I made it quiet by replacing all fans, installed Noctua NH-D9DX i4 cpu fans and sq power supplies. For the most part, this works well, cpu temperatures are between 30 and 40 degrees C, so are the hdds, some ram modules are above 40 degrees C. The only hot spot is the 10g nic which is constantly around 70 degrees C. It's in the top left corner if you look at this picture, there's no place to mount a rear fan.

As you can see, the heatsink is where the PCIe slots are, so it's right under the SAS card, an LSI 9201-16i. The drives connected to that card are rarely under high load, often idle, it used to be in the same place on an older but similar mainboard, but now it's right above the heatsink of that 10g nic. I'm looking for ideas on how to improve this situation in that corner.
I should note that the onboard nic is not used for 10G networking. If I wanted 10G networking, I would use SFP cards, which I already do elsewhere, those do not get hot at all. Unfortunately, when I picked the mainboard, I didn't notice that it has copper 10G networking onboard.
Any ideas?