Before when I had the 1080 it was flipped the problem is at that time it make the cpu hotter like 7-10 degree more hotter than now, I'll try it today and see , so it seems it's airflow issue?
1)Well, your ol' 1080 also:
-didn't have 24GBs of GDDR6X Vram, which has higher operating thermals than the 8GBs of GDDR5.
-wasn't anywhere near the same level of power draw/heat load either.
2)It's a poison pill just about everyone has to swallow: Do you prioritize cpu thermals at the cost of gpu? Or do you do vice versa?
It's going to go one way or the other - can't have both.
The cooling tradeoff/penalty is usually minor, but in this situation, there's a 3090 in here...
For the cpu: if you wanted to prioritize its cooling, you should do away with the top fans entirely.
It's fan already draws air from the front and top. With the top intake, you've got air coming from the front being pushed down and away from the cooler, as well as interfering with the flow of exhaust off the back of the cooler.
The folded sides of the Noctua cooler also work against it. This design promotes more front to back airflow, but reduces the effect of top intakes placed above it.
This is less efficient than having no fans up there.
If you did rear exhaust and a single top exhaust, that's also less effective than just having the one in the back.
For the gpu: with a card that dumps its waste heat in the chassis, you need more exhaust to get that out effectively. So, rear and top exhaust.
Top intake air running into gpu exhaust, you're causing it to take longer to get the heat out of the chassis = less efficient cooling setup.
Blower/Turbo gpu: doesn't dump its heat in the chassis.
Hybrid gpu: a well designed hybrid won't signfiicantly heat up the inside even if the radiator were positioned to front intake.
Custom liquid: same deal with hybrid... sort of.
Top intake isn't so bad with the above, but your gpu isn't any of those.