Playback quality stuck on Full and Playback is extremely choppy

In addition to the questions posed by R Neil Haugen , how full are your drives? 

We have first no evidence that your "insanely powerful" computer is ... anything. And many times that sort of phrase has been used, and when we got the actual, usable details, it was a six year old laptop. NOT powerful, in fact, pitiably so by 'modern' computer standards. Which are always shifting, which is a total pain.

So ... troubleshooting requires accurate, full details ... always. Period.

OS/RAM/GPU/vRAM, GPU driver, and what type of drives ... SSD or old spinning HDD, and internal or external?

Next, the media used for format/codec, framerate & framesize, created by what? A screengrab of MediaInfo on "Tree View" showing your video media file's data header is great for that.

What effects are you using?

Give us that and we can help.

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

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