Hi,

I use my NUC (BOXD54250WYKH1) primarily as a Media Center + server and am experiencing the fan running very loud quite often.

I changed the BIOS settings for the minimum duty cycle (fan speed) from the default 40% to 20%  (which is around 1800 RPM) - at this level the fan is barely noticeable. However, the fan starts running at high speed when the CPU heats up to around 65-70C with some load. This in spite of having my BIOS settings set to have a 'control temperature' of 80C (which is what the fan is supposed to target) and max temperature of 90C. In my mind, as long as the CPU temperature is below 80C the fan should run at the minimum level - however, as mentioned, it starts running at max around 70C.  The secondary control temperature is from the motherboard, however, I have the tolerance levels set well above what this temperature ever reaches.

I want my NUC to run as quietly as possible. Any help much appreciated!

I'm running the latest BIOS firmware on Win 7 64-bit.

Thanks