10Gb/s Ethernet: using mini-heatsinks with a 10GBASE-T SFP+ module

In my last post I showed the somewhat-scary temperatures I was getting on the MikroTik 10GBASE-T SFP+ module I have plugged into nigel, the 10Gb/s switch I have in my study. As I mentioned then, the plan was to try using some of the mini-heatsinks that people use on Raspberry Pis, to see if that would help. Here's how it went. I bought a 40-piece set of heatsinks made by the improbably-named VooGenzek on Amazon for €8, and attached two of them like this -- see the bottom module, with the yellow cable: That was 24 hours ago, and here's a chart of temperatures from that module showing the 24 hours before and after: You can see the big drop-off in the middle of the chart; it even overshot a bit (I'm guessing because the heatsinks absorbed a bunch of heat initially when I put them on). The difference looks more dramatic than it is! See where the Y-axis starts. But given that the weather has been pretty much the same today as it was yesterday, that looks like a 3.5°C improvement. Not…