I have the N305 25Gb version and the N100 10Gb version. I also have the first gen N305 which was just a R86S repackaged in a 1U chassis.
The N100 has been problematic and I've been going back and forth with David about it. I was hoping that STH was going to review the N100 also, to see if the issues I'm seeing are common. This was going to be my new baremetal Opnsense FW, but it's just sitting on the bench for now until I have more time to deal with it.
The N305 version on the other hand has been pretty great, after a little rework. The PSU fan is the only noise you'll hear, after swapping it with a Noctua fan, it is now silent. CPU temperatures were a bit higher than I would have expected, so I started investigating. The thermal paste on the CPU was a mess, replacing it with what I deemed to be an appropriate amount of MX6 resulted in higher temperatures and after disassembling again I could tell that that heatsink wasn't making contact with the CPU. I tried out gap pads and copper shims, similar to what people are using on the CWWK fanless units. I ended up using a 0.3mm shim with MX6 and CPU temperatures are about 20C lower than when it arrived.
My absolute biggest complaint is that these units are larger than 1U tall. 1U is 44.45mm which means that a 1U server should be around 43.45mm or maybe 43.95mm if you really want to push it. Both of my units are >45mm which means they cause interference when mounting in a rack. This problem isn't exclusive to Gowin, I have a different cheap 1U chassis that is also too big. In a lightly populated rack this wouldn't be a big deal, but I try to keep my rack nice and use blanking panels in empty slots. I now have to leave a U open becasue the stack of 1U servers push down and the blanking panel no longer fits.
The fanless unit doesn't fit a use case I would have, but the idea of a large heatsink could make for a better fanned unit. Reorient the fins front to back, put the full top cover back on, and add the chassis fans back in.
