[rescue] loud fans

[J. Alexander Jacocks]

Ryan Thoryk <ryan at tliquest.net> said:

 > I was wondering if anyone here knew how to solve this problem.  My Sun
 > Ultra 2 has extremely loud power supply fans, and I could've sworn
 > they used to be quieter about a month or so ago (???).  As you know
 > the Ultra 2's have 4 fans, 2 on the left for the RAM and CPU modules,
 > and 2 in the power supply in the back right.  My SGI Indigo2 is really
 > quiet compared to this machine...anyway, is there a way to change the
 > fan speeds, or replace the fans (this would also be good info for
 > people owning older machines with insanely loud fans).
 >
 > Ryan Thoryk
 > Unix and Network Specialist
 > ryan at tliquest.net

If you think an Ultra 2 is loud, try having a CycleQuad on your desk. 
<grin>

I asume that the bearings in all of your fans are OK.  Flat 
bearings/bushings will make a fan _really_ loud.  Other than that, you 
can try replacing the fans with others with greater or equal CFM 
ratings, but that would be a bit of a pain.