Hi, so i have found an option to change Maximum Fréquency in %. I guess my GPU (RX 580) does at maximum fréquency something like 1366 MHz. How much percents does i have to side down to attain a stable 918 MHz maximum. Thanks.
Radeon Settings comes with AMD WATTMAN which you can use to configure your GPU card. See if that helps.
I have found a solution. Thanks.