I have a 1k RCT for my internet and the fan drove me nuts. I emailed Firstshop and they approved a return and 'fixed' it, but it made no difference.
I tinkered a bit, warranty now void, but I have not heard the fan since said tinkering. A big contributor to the noise is the mesh covering the fan, so I cut that out. I also installed a fan that runs a bit quieter, but I don't think it has actually come on yet.
The biggest problem it seems is the heatsink to which the thermal sensor is connected, it needs some breathing room... while testing the new fan I left the cover off and the fan wouldn't come on. Put the cover back and not 2 minutes and the fan is spinning like a Chihuahua with rabies. Cover off, no fan for hours.
I took the cover, removed a few bits and I can honestly say I have not heard the fan come on yet. My RCT is now a R||||. The heat sink is just to the left of the vents.