anybody ever make a 'chimney' or 'heatstack' for their case?

[ClockHound]

#1. ok, oddly, turning off the rear fan makes 3C difference in temperature. I thought replacing the top two fans with dual Aerocool Shark fans would be enough to move the hot air out the top but -NOPE-. Why? Because, #2.

#2. I think I will be careful before buying a case with metal and/or plastic mesh over the fan holes. Those make a huge difference in airflow. Right now I have the CM690

#3. For now I am going to cut out the metal mesh at the top and bottom. I need to get a tool to help me smooth off those edges. I'm going to cut myself for sure. I kid you not, max temps of 61C full load 100% fans at 4.6ghz/1.44v, and 58C with the rear 120mm fan running. I could design such a good case based on what I know now...and frankly, you should now leave the fan installation up to the user. The users are too dumb. Actually, maybe you should, because it gives them opportunity for growth. I had total n99b fan placement until I started all this testing.

I no longer run exhaust fans in most of my builds...but I do cut out the grilles, remove PCI slot covers and backplates. I do this not because of my tin-snip artist aspirations (too long repressed) or for the sheer emotional satisfaction (it is gratifying), but for the 2-3 degree reduction in peak temps when the cooler's fans are spooled up. And reduced fan noise. This open-air, case breathing mod assumes a clean front to back airflow. I'm more concerned about recycling hot air inside the case than in the room. If I need less hot air in the room, I can always shut up. (Not always...but still...)

A good old read on the evils (sometimes necessary) of case grilles is here:
https://www.pugetsystems.com/labs/articles/Effects-of-Grill-Patterns-on-Fan-Performance-Noise-107/

tl;tr: The old skool open round grilles disturb airflow the least.

Interesting observation about the 'windy bus' - I like that. I've migrated intake fans to PWM models controlled by the MB CPU header using a splitter. At idle with the cooler and intakes spinning sub 300rpm, it's silent. When the workload increases a gust of PWM-driven cool wind slowly exhales into a fresh breeze. After the gale of render work is complete, the system sighs quietly back into silence. It's not quite as poetic as it sounds...;-)