i could swear this question was made this same week
https://www.youtube.com/watch?v=X6EilqPFHpg
that is not a s, so expect a bit lower performance, gta v asks more the cpu than the gpu
try to add if possible, more ram, gta v does like lots of ram and will use as much ram as possible, with 8 gbs i see gta v using 6.5 more or les,, if it had 16 it would use 12 or more