Speaking of PCs, anyone here who has experience with air cooling? I got 4 Arctic P12 MAX fans for my Corsair 4000D. Some have said about putting fans on the top of the PC being a detriment to cool air flow or whatever and some have other setups. This is my first time doing this so I want to hear from some kiwi experts on how to do this properly. Yes I'm still keeping the stock fans. They still have their use afterall.
The main thing you need to think about is making sure the air comes in, passes the GPU and CPU, and then is expelled. For example, the conventional setup is intake along the front and exhaust at the rear and top. That way the GPU gets exclusively cool outside air, which is exhausted through the back before it can enter the stream of air the CPU takes in, and the CPU's air is exhausted out the top never coming anywhere near the GPU. If you have hard drives, letting cool air pass them before entering either the CPU or GPU is ideal, they don't put out enough heat to impair those hotter components much, but they will still benefit from the cooling themselves. Another common approach, particularly in SFF, is intake on the bottom and sides, and exhaust at the top.
The most important thing to consider is leaving room around the components. It's pretty common nowadays to mount GPUs vertically, but if a vertical mount smushes it up against a glass side panel, airflow will be severely impaired. Components should have ample room around them to avoid this issue. If you want to maximise your air cooling, make ducts out of cardboard (or 3D print them) so that you can direct and compartmentalise the air.
For the Corsair 4000D, you should use the front and bottom as intakes, and the back and top as exhausts. Make sure you mount your CPU cooler such that it's aligned with the airflow. The intake fan should point at the front and the exhaust fan at the rear, it's a surprisingly common mistake to mount the cooler upside down such that it's blowing against the airflow of the case, which will harm cooling. Also don't fill the entire top with fans. A fan at the front top of the case will just exhaust cool air, which is completely pointless. Air should pass a hot component before it gets exhausted. With four fans, I would put three at the front and one at the rear. More intake than exhaust means you'll get a positive pressure inside the case, so there will still be air exiting at the top, but you'll make sure more of the airflow is directed toward the CPU and GPU. Also remove the dust filters from any position that doesn't have an intake.
