Should I see a temperature drop...?

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I have a new build with a 5900x and Dark Rock Pro 4 in a Lian Li Lancool II mesh.
If I gradually increase the load on the CPU I hear the fans ramp up (both fans on the Dark Rock and all case fans tied to CPU temp - I use 60C as the trigger temp in this case). However, with no change in the load the temperature does not decrease at all. Neither does it increase. I would have expected the temperature to drop a little as as the fans shifted more air. Is this a correct assumption? I started to wonder if I fitted the middle fan of the cooler the wrong way round so it is fighting the main fan air flow, but temps do not get excessive so not investigated further - yet.

If I decide to remove the cooler to check it out I want to replace it with the best thermal paste for the job so any recommendations there would be gratefully received, especially from people with the same components. However, I don't trust myself with liquid metal types.
 
Soldato
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However, with no change in the load the temperature does not decrease at all. Neither does it increase. I would have expected the temperature to drop a little as as the fans shifted more air. Is this a correct assumption?
Errrrrrrrrrmmmmmmm yes... sort-of... There will be a base level temperature at which your CPU idles, no matter how much air you put through the cooling system. It's not really a 'cooling' system either, so much as a way of getting rid of excess heat, which is a better way to view things.
So long as your temps are within general spec, you should be fine.
 
Soldato
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Sounds like you have case fans setup to supply air cooler fan/s need so as temps rise and fans (cooler & case) speed up they keep temp from going higher. Best way to find out is play with temp to rpm curves and see if setting fans to spin up fasters / spin up to higher speed at lower temp helps. For me, ideal is at maximum normal load fans remain inaudible / barely audible at temp 20-30c below throttle temp. On my 3600 this is fans at 750-800rpm with 65-70c temp. Think 3600 throttles at 90-95c. In normal use fans run 400-600rpm with CPU 35-45c.
 
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Thanks doyll, I have a temperature curve set up and have the fans going to max at 85c for the 5900.
I have CPUtemp running and I have never had it record a max of more than 82c if I remember correctly. But that is running stress test software.
Cooling isn't an issue but I have yet to get the cpu to do some proper work with, say a 4k game on ultra settings, but I can't do that till I finally get a 3080.
My original question was around not seeing a temperature drop when the fans kicked in and there was no additional load. But that was answered a couple of posts back.
 
Soldato
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Indeed, fans speed up as temps rise. If setup correctly temps don't drop. That said if system goes for idle to 100% CPU load (stress test) the temps will them sometimes peak and drop down a few degrees in next couple of minutes. This is because CPU heat increase is from 30c to 80-90c full load in less than 1 second, and case airflow takes 10-20 seconds to ramp up to match cooling demands .. thus heat jumps faster than airflow and it takes airflow a little time to balance temps. From you post it seems your load is not instantaneous, but gradual .. meaning fans / airflow is ramping up same as temp is.
Hope that make sense.
 
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