Case Fan Placement

[Azrael]

Case Air Flow

The thing all overclockers, and most other people, are worried about; Heat. It literally kills and isn't good for your computer's parts. Sure if you have money to burn you can always get super expensive cooling set-ups and all that jazz, but for most people with air cooling or even water cooling, case airflow is key.

The Problem:
Every component in your computer produces heat, it's the problem with electrical constructs, as no element has a o% resistance when electricity is passed through it, there is electrical energy lost, and since you cannot create or destroy energy (well that changes with quantum physics... but you know), it becomes heat energy. This of course permeate your whole system causing more heat... it's an ugly mess. Even water cooling can't cool everything, there is always going to be heat (and no liquid Nitrogen around to cool it ).

The Answer:
Lucky for us the air in our hot cases absorbs the heat (althoguh it doesn't take much heat energy to make the air the same temperature, but more on that later). This allows us to do something, to move the hot air out of our case and replenish it with cooler air from out side the case (I hope it's cooler out side...). Now because air doesn't absorb much energy, it takes much more air to remove all the heat being continuously being created by your components. This is why you constantly take air out ans replace it, so that it flows, kinda like a river (or water cooling ).

How?
Well sounds easy enough just slap a good number of fans on your case and bye bye heat. For one, no matter how much air you get rid of, your case will be limited to the ambient temperature of the area where your case is located. Secondly After a while adding fans does very little to change it (besides the fact that it may cause other problems). Lastly you need to create a continuous flow, like a river, and get rid of all obstacles so that as much air can move at once.

I) Make sure you know what size fans your case can take because it'll save you trouble later (you can always makes holes, and such but not everyone can or has the want to). Fans come in many sizes and kinds. The most common sizes are 80mm (8cm or a little more then 3"), 92 mm (9.2cm or 3.5") or 120mm (12cm or a little less then 5'). These are normally written on the fans and are the width (or diameter) of the fan's inside edge (where the blades spin). There are also different kinds of baring and such, but that has to do with noise and longevity of the fans. The bigger the fan the more air is moves around, and often the lower speed it has to spin at, reducing noise.

II) Know which direction the fan blows, so you can know how to place the fan to make it an exhaust or intake fan. (Exhaust takes hot air form inside the case and blows it out, while intake takes cool air from outside blowing it in.) This is vital for the air flow. Also, always keep in mind that hot air rises (as it because less dense and other such fun physical characteristics).

III) Make sure your cables are tucked away, use twist ties, elastics or even string to ties your wires together (making them round-ish so that air passes around them easier), and try to place them out of the way (watch out for ribbon cables... they are especially bad for air flow).

IV) You want the air flow to go from the bottom/front of your case to the top/back of your case for best results.

V) Please regularly dust your system, dust is a major cause of heat build up as it acts like insulation, keeping heat on components and can lead to damage. They also impede fans by causing resistance to the spinning blades.

Installation:
This section will be divided into the optimum placement and direction of the fans according to how many fans you have.

1 fan:
With one fan that best possible area and alignment to place the fan is as a exhaust at the rear of your case, right under your Power Supply. This will make the fan run parallel to the fan in your power supply's fan 'doubling' the effect of the exhaust. Make sure there is enough ventilation holes other places in your case so that the air can enter as well. The worst thing to do is create a vacuum in your case (stationary air, which the air in your case will then act like, is a very effective insulator [that's why double paned windows work]).

2 fans:
Place one of the fans as before in the rear of your case right under your power supply (exhaust). Then with the other fan place it at the front of your case (there usually is a place on the front panel at the bottom. This fan should be oriented as an intake fan. This is a pretty good set-up, as the intake fan will aid with the balancing of the air going out/in.

3 fans:
This is the optimum mid-end flow pattern possible. Place the other two fans as with the two fan placement. The third fan will be placed as an intake fan on the bottom, near the front of the case, sucking in air from under the case (make sure you case is a little off the floor so that the fan actually can suck in air). This is great as it balances the intake and outake perfectly (counting your psu as a fan). This works best with fans of similar size and speed.

4 fans:
This is slightly difficult to judge, normally if you do more then three fans you go right to 5, because it works the best out of all the placements. but if you think it'll work you can tries these two approaches.

I) Place the other fans as previously described. With your fourth fan place it on your side panel over the area where your video card and pci peripherals would be. Set it to intake. This, if your exhaust fans are strong enough, will cause the heat generated from your video card and other cards there to be passed into the air flow (althoguh it disturbs the flow as it blows it everywhere) and taken out by the exhaust fans.

II) Place your fourth fan at the top panel of your rig to act as a so called 'blow-hole'. This is a good place as it stays wit the front-bottom to rear-top idea. The only problem is it can cause a vacuum affect and as previouly said, that is a bad thing.

5 fans:
This is, in my opinion, the best way to make the air flow through your computer. I'm sure there is a better way, but this makes sense to me. This is real simple; place your fans by combining 4I) and 4II), that is to say have the intake fans at the front panel, the bottom and the side panel and the exhaust fans at the back panel and the top. This creates a great airflow in your case quickly pushing hot air out and cooler air in. This can get kinda loud so it's best to have large fans (120mm) that are fluid or ball bearings, these will create the least sound for their capacity to move air.

Final word:
Remember if the ambient temperature in your case is lower, your components will be at a lower temp. All those heats sinks use the air inside your case to release the heat, so the cooler the air, the more heat absorbed. This is more of a newbie guide to air cooling as I only spoke about overall case airflow, and I don't feel like describing how to cut a nice hole in your case, I'm sure you can find a guide on that somewhere.

Lastly remember that if you have one of the two balanced systems to cover any holes in your case, as air acts like water and electricity; it takes the easiest route. which is not always the best as if a hole is near an exhaust fan, air will be coming from that hole and not the other fans. This is only for those with balanced fan set-up such as 3 or 5 fans, as the other require you to have such holes (but try ans keep the holes in the front-bottom to rear-top format.

Well I hope I helped, This should keep your temps lower and a better overclock, or just a healthier system that'll last longer.

~Azrael

[Tefra]

Sticky and rep for you

[weasel]

very good read

[Azrael]

Thank you, I though of this during my research on my possible new cases, and the case I selected has these places for the fans. I was also doing calorimetry in my chemistry class, so a little thinking and some common sense and boom (plus I tested some of it on my bro's computer for good measure).