Massive fps drops / texture loss / sutters on good pc

Are you using direct x 11?
You can try uninstalling rockstar launcher and install again,
another option is to check the integrity of the files in steam

If you can problems with your fps, you can check this [Release] FiveM for Low End PC"s (2.0)

I insist, from what I see in the image, I see related to a problem with sync but I’m not sure.