Realtek PCie GBE Family Controller. How to set a static speed of 100 Mbps if it constantly drops to 10 Mbps?

Question

network hardware

When you turn on the computer (motherboard ASRock AB350 PRO 4) , there is a problem (not every time, but about once every 5 turns on) that when the Internet speed is 100 Mbps, the network adapter drops to 10.
This temporary problem is solved by changing the value "speed and duplex" in "Properties"

The problem repeats when you turn it on again and the value in "Properties" does not change, that is, it remains at 100 duplex.
When you change it to the "Auto Negotiation" value, everything changes to 100, but then the same problem
Drivers are fresh. I tried to download and reinstall them, nothing helps!

Answer 1

99% the problem is in the physical environment. Cables or connectors. The first thing to do is to re-compress the cable on both sides (unless, of course, you have it 80 meters or more).