Where's the cool PC edge? Many companies prefer "more is better", but this is probably not true in computer science. The inside flow of the box is obviously dictated by the features included in it, but when we talk about the chimney effect and the floor effect on PC fans, it's all complicated.
Choice of chassis is more decisive than putting fans down
It's not surprising to find meetings that have a false spirit, where it is sometimes more damaging for fans to go astray than to not have them directly.
Floor fans, also called floor fans (not because they are different from everyone else, but because of their position on the chassis) are a perfect excuse for broken or unrelated equipment flow.
The Chimney effect systems, as a rule, are carefully selected to improve the effect of temperature increase, are less dense than cold air, and where fans of 20 inches or more are often used to increase flow and reduce noise.
If our tower does not have a vertical release of air in the push / pull configuration (floor and roof respectively, not the pressure / pull on both sides reasonably), we may be facing a basic configuration problem.
Fans at the bottom of the box: best to avoid them or, at least, always on stress and undue stress
If we search the Internet we will conclude that most of the boxes and assemblies they deliver are poorly prepared. Currently there are a few models that allow fans to be low and are highly tuned to pressure drop and pressure, that is, by introducing cold air from the bottom of the tower.
The theory tells us that cold air is very close to the ground, so getting inside the bot tom of the tower should be an advantage. But the fact is that when there are no 5.25 bays and the introduction of front panels and fans to their credit, this kind of encounter completely breaks the flow.
The dry and cold air from below makes the curtain inaccessible to the front fans, which, too, as a rule, in the air-conditioning arrangements go into the tower. The problem is that there are many differences between each other, they are very small, but it is enough to create a particular curtain on elements such as graphics cards.
So, we'll have a set of well-organized streams: that graphics card itself, a heatsink or AIO and some PC fans. The graphics card expands its flow directly and in opposition to the front fans, the fans of the apartment throw cold air up and drag the hot air from the card to the roof and the front fans try to overcome the dual pressure of the air back on the chassis.
What we will gain by positive and negative pressure is to create a a whirlwind inside the tower which will increase the internal temperature of the chassis to a certain extent because we also do not cool and do not allow its easy removal.
So, doesn't it make sense to put fans down?
In positive pressure and press no, in negative pressure then press yes. In this last setting it does not significantly interfere with the flow of fans at the front of the box, it collects some of the hot air left by the motherboard with a chipset and graphics card and thus reduces the interior temperature of the tower.
It's not a very good place, which is doubtful enough, but in some cases useful for most users would be grateful.
If we also prefer custom cooling, this step is better for improving temperatures, because although popular belief is maintained, good results often come with negative pressure when pressed, where the hot-air intake of radiators is the best example of possible heat today.