After Effects won't stop RAM previewing

How do I get After Effects to use the full available RAM?

I have the following configuration:
Ryzen 9 3900X processor
RAM: 128GB
Graphics: MSI RTX 3080Ti
OS: Windows 10 Home

In After Effects, 12GB RAM is set for other applications. Only After Effects launched. The system cache and the cache of the entire Adobe software are on the m.2 SSD disk. (ADATA) 500GB. Cache After Effects is allocated a size of 300GB. The disk is not full. I emptied the memory, I cleaned the cache.
After Effects doesn't want to use RAM. The maximum use is around 20-28GB. Much has been said and written about one CPU thread in After Effects.
I am asking what's wrong with the system, what am I doing wrong that the RAM is not being used?
Other applications such as V-Ray for Cinema 4D, Cinema 4D can use the full hardware resources of your computer!
Why do I have to wait a long time for the rendering of the 2D animation using the Ae + Me duo ?!
During rendering, CPU usage is 6-10%, GPU usage is 5% !!!!
The computer is BORED !!!
We are in the 21st century and Adobe After Effects is designed to run on laptops from 2008 !!!
Why an investment in hardware, memory, multi-threaded processors? Why if all this is not used ?!
Clients are waiting for projects, I have to explain myself stupidly. They won't understand that the software is not ripe for the hardware !!!
Please help!!

Best,

Krzysztof

Same issue here! I am happy to here that Windows users found a fix for this - but what about us Mac users? I'm on a MacBook Pro with macOS Catalina, and Mac doesn't support Nvidia anymore, so we can't do it with a update. Anyone having a solution to this, until Adobe fix this annoying problem?

Thank you!

So you swapped out your MB and CPU without doing a fresh install of your OS?  As far as I understand (i'm no hardware wiz) this is not ideal and can cause driver conflicts and hardware failure.  You basically got a new computer and just plugged your old hard drive into it.   There are videos of ways around doing a clean OS install but even if you do this perfectly there's still a chance of failure.   If you get a new a computer you should really do a clean OS install.  I may be wrong.