Silent CPU?

Hey thanks for the link!

I'll look into it for the next build, however as I said the sound was coming from the screws vibrating against the case, so the fan itself was not the problem.
 
Water cooling is the way to go if you can afford it and are okay to tweak a little (but kits are easy to install). It's really efficient.

Also you could control yourself the fans and the temperature of the CPU. On my previous computer, it would almost never go higher than 35/40°C, so I lowered the fan speed to reduce the noise while still maintaining a decent temperature. On my current mac book I did the exact contrary cause I prefer the CPU temperature to stay in control, cause the fans are not that noisy, and it's better than hitting 70 or 80°C and having the fan accelerating like crazy to lower the temperature in 1 or 2 mn.