PC cooling help

[Exploration]

Personally my rig consists of three 120MM Artic Intake and one 92MM Artic Exhaust, though i do have a PSU which also helps in the exhaust sorta area since it's top mounted and has a fan which sucks air from inside the case also though i don't count this 120MM.
With proper configuration, it can run quite quiet. Granted it took me about 35 minutes to get the software to control them properly. In my experience, having bigger fans which run slower is efficient and quiet, running a stock cooler i notice a huge difference since the two side mounted direct airflow at both the CPU and the GPU, reducing the strain on thier own respective fans so they also run slower and quieter.
Cleaning though, regularly makes most of the odds for me. Pulled my Heatsink off after 6 months and found 8MM of dust under it, literally. So now i clean it every month (This is just the design of my CPU cooler) It seems to trap dust between the heatsink and the Mobo and it just causes it to cook. Probably should invest in a new cooler for that soon, but meh. It's not let my CPU temp get above 38C, so i'm not gonna bother.
Finally, i buy decent thermal paste and change it every 6-8 months or so. Again Artic brand, all thier cooling gear hasn't ever been a let down to me