How to connect 2 monitors with different hertz and what problems can arise?

Question

Video cards

In general, the situation is this.
For some time I had two DELL P2418D 60Hz, I recently purchased a samsung odyssey g7 and it replaced one Dell. After that, on the Samsung, I set it to frequencies of 144 -240 Hz.
Everything seems to be working, but I noticed that the Memory clock always keeps at the maximum of "14002" and the CPU clock also jumps almost to the maximum of "1215 out of 1605"
Then I tried to disable Dell and the Memory clock fell to a minimum of "810" and rises only if something This happens on the screen
and the CPU clock is also kept at a minimum of "300".
If you set both monitors to 60 or disable one of them, then the problem disappears, but still I would like to have 2 monitors.

In this regard, there are several questions:
1. Do I understand correctly that the video card is very stressed and there is no way to avoid this when working with 2 monitors with different Hz?
2. Is it dangerous to leave things as they are? Will the video card die after some time at this pace?
3. What are the ways to solve this problem? for example, connect another video card to hang dell on it, but samsung remained on the main one? or buy a second samsung and put both on the same frequency?

Computer hardware:
Motherboard Asus ROG Strix Z390-E Gaming
CPU Intel Core i9-9900K, 4700 MHz
RAM: Kingston HyperX 2x16 GB
Video adapter: GeForce RTX 2070 SUPER (8 GB)

Watched frequencies through Asus GPU tweakll

Please help with resolving this issue. maybe i missed something somewhere?

Answer 1

I vaguely remember that such a problem was due to the fact that monitors with different frequencies somehow forbid the video card
to use sleep