I've tried to do a bit of research and it sounds like it's fairly straight forward to control a PMW fan with an arduino. But I've seen some suggestions that arduino's may not be able to deliver fast enough PMW speeds to allow fans such as this to perform at their full potential (which I will require). Is this true?
If you simply use analogWrite() the PWM frequency is set to 1kHz which is not sufficient for operating the PC fan. But you definitely can achieve the needed 25kHz signal with the hardware of an Arduino UNO.
If I can properly control these fans with an arduino (Uno is my intention), how would you recommend I power the fans from the mains power? Should I just get a basic computer PSU, or is something else more suitable?
I would expect your 3D printer to already contain some sort of 12V power supply. If ever possible I would use that one.