Yeah Yate Loon, yes yes, monty python you are on your own, Firesign Theatre now..
To point, the case designs are chaning two ways, filtering more air [ more mesh convering including filters] and more fans.
Cooling still reqires air movement, hopefully cooler outside air, reaching all components.
Going from BTX to ATX required major revisions in air flow fans and heatsinks.
We are leaving an era when Overcloclocked CPUs might use 200 watt capable coolers.
Generally:
Going into too much detail is off puting, basics include measuring changes, and learning the basics of picking a fan.
Details are fasinating or boring, depending on interest.
If you look at White papers on P4 or AM2 140 Watt designs from ten years ago? they changed case design. Remember air ducts?
The power supply was about 50 to 70 % efficient and moved air for both the case and the power supply.
80+ DESIGNS often Do Not run their fans until reaching half or more of their rated wattage. The day of a power supply contributing to case cooling is pretty much gone. IF YOUR SYSTEM averages 300 watt (high these days) at 85 % that means the psu is only "wasting " 45 watts to heat. Think of a small light blb with heat sinks.
The CPU's, even the video cards involved have reduced the current used.
Generally adding a fan to a case which is ready for one is simple, and only requires a decision on direction of flow. You can find filter assemlies for $4 or $5. A fan, depending on features $5 to $25 or so.
Most sleeve bearing should be good for at lest 20,000 hours. That's at 8 hours a day 2,500 days, just under 357 weeks, which is 6 years. Or two years at 24/7 use.
You can spend more upgrading fans than you spent on your case.
Usually Cooler Master does a fair job on air flow. And like most cases, cost dictates acessories. YAH>>>???? pay less get less
As for over pressure, my reading/study supports the idea air entering the case should be filtered, to maintain long term cooling ability.
AT fan capabilities air is pretty much an incompressible fluid. Inlet fans primarily just insure airflow enters thru filters when it attempts to "fill" the case with air.
The exhaust fans do most of the work. This airflow among all components is critical.
This is why cable routing/management is important.
Yes Antec Tri-Cools are good fans and offer three speeds. Some people find them loud at full speed, depending on case.
Yes THERMALTAKE makes some excellent fans, but I don't know their best from their worst and their prices and specs do not always match expectations.
So, let's keep the air moving, boys and girls.
FWIW I worked with a Hot Isostatic Press for almost three years, an Autoclave water cooled pressure vessel electrically heated to produce micrograin carbide cutting tool bits.
Pure Argon gas was pumped in then heated. At 1336 degrees C 20,000 PSI (i forget the Bar). Magnetically powered internal fans. The lid weighed about 1200 lbs, was on a pneumatic ram, thread was a one inch steel cable.
Original containers were a steel bucket assembly lol at 2600 degrees F three quarter inch wall steel pots "belled" out. Went to graphite.
Know a little ..