Low-noise fans for Sun 1U rack server?

I use a Sun Fire X2100 M2 (Opteron) 1U rack server for development purposes, and the system has these noise specifications:

Idle, at or below 25° C 6.9B Max, at ambient: 7.3B

In other words, it's rather loud and I'd like to bring the level down somewhat, if possible, by switching to low-noise fans.

My questions, in order of priority (descending): - Which low-noise fans suitable for 1U rack servers are out there? - Can you recommend any of those over others? - Are fans standardized in a way so I can be sure they'll fit before buying some? - What kind of decrease on the noise level could I possibly expect?

Thanks a lot in advance.


Most of the noise isn't from the fans, it's from the actual flow of air. So for the same amount of cooling, you won't have much of a reduction in noise level. This is important because there is no room in a 1U chassis for heat to dissipate. If the air isn't moved fast enough heat will build up very quickly. This is bad for two reasons:

  1. The server might overheat.

  2. The top and bottom of the case might become very hot and transfer heat to the servers above and below. So the 1U servers are built to force all the heat out of the back of the machine. If they weren't, they'd cook the other servers in the rack.

If your test machine is on a desk somewhere, you can try finding the specs of the fans in a catalog like Digikey's and buy fans that are the same physical size but that have lower RPM and hack the fan modules. This will void your warranty and the reduction might not be all that impressive.