Noisey cmptrs annoy me. I'll suggest a laptop. They generally have engineers designing them. (as apposed to coolcollar desgners

) As such laptops often end up with smart thermal management. . . .Thermal sol'ns like lower voltage chips, and heat-pipes to high surface area exchangers. (High heat-transfer surface area is key to quiet.)
Fans make noise. Adding fans gives more chance of componding the noise, as they 'sing' off each other.
Here's a pic of one
cool little item in my Dell notebook. (fits on the GPU, if I remeber right)