Head to Neck Texture Not Smooth and Can See Seam

I have a new asus gaming desktop pc & better nvidia card, & crack still shows up on necks & even on back of lower legs, & some foreheads can get a little crack mark while in CAS, depending on the hair, also some hats have had cracks in CAS. Don't know if everyone has this problem, or if it depends on graphics card, or if it could be a result of playing in windowed fullscreen mode?..🤔