I also started to have this kind of problem on my Gigabyte x470 Gaming 7 for one or two last updates - various fans are periodically dissapearing from monitoring, it sometimes displays like it was reset to 0 or goes up to unrealistic values (my pump is 5500 rpm max and it shows it's going up to 16K rpm or something like that) , temp sensors are disappearing sometimes (or show strange values, like water going up to 55C or so, which is impossible unless the pump was stopped but somehow hot water was still going through the loop), fan sensors that do not exist also appear sometimes. The board has ite 8686e and ite 8792 SuperIO controllers