I have a mix n match of fans for my Fractal Design R5 consisting of the following: in the front blowing in are 2 140 Phanteks fans. on the cpu heatsink there is just some regular 140 fan facing the front fans whilst pulling so its directly pulling the air from the front fans air which is being blown in at it. Ok Then last fan is a fractal 140 fan which is behind the heat sink but attached to the back of the case and blowing not pulling the air out of tyhe back as exhaust. Now I understand this is a very poor put together post Im just completely lost on what PWM and the other couple are and do I need them and what should I do about Push Vs Pull and maybe sometimes Push+pull? Anyway please if someone can take a few moments please help me understand this better or tell me if im just missing something altogether. Thanks loads mates!