Mine is a fairly reasonable noise level. Two QSFP+ 40GBASE-LR optics, two 10GBASE-LR optics, two 10GBASE-T.
I haven't confirmed this, but I have to wonder if it uses SFP temperature in setting the fan speed.
I just got mine a cople of weeks ago. This does indeed appear to be the case.
I have one SFP+ module (Mikrotik S+RJ10) which will run hot (50+C) no matter what you are doing, and when it is installed the fans get louder.
Everything other module in the switch - even the QSFP+ ones - sit at ~30-32C.
I had actually bought 3 40mm Noctuas when I bought the switch, but ended up not bothering with the fan swap.
A 1U switch like this will use noisy fans for a reason. They need to move a lot of air to keep cool under load.
I would worry about using less capable fans, just in case something overheats and becomes unstable or is damaged. Of course, the fans could just be noisy because they are cheap and poorly designed.
Does anyone know what the air flow and static pressure ratings are on the stock fans? It would be interesting to compare them to the likes of Noctua's 40mm fans.
That said, ambient is ~22C in the server room right now, and the transceivers all have temp limits that are 85+C, so if the room gets hot enough that those modules are overheating, I have bigger problems...
