I noticed when (Smart Access Memory) SAM mode is on, Apex Legends game, flying and landing is observed 20-40fps, and on the ground 60-100. SAM mode is disabled, the performance is smoothly 100fps, on the ground landing 144fps what is the reason for the SAM module problem. My videocard rx6500xt
Some games do not perform well with it, just happens to be apex is/was one of the worst from some reviews i read.
Maybe you should read some of them so you know what to expect from certain games (that were tested).