As discussed in the other thread you started, this is, imho, not the way to go. If you are willing to play at 30fps then sure, you could do this, but I honestly run a spec that is slower than yours and I am able to get much more than 30fps - average closer to 60fps with most busy dips into the 40s and I can watch netflix streaming on a second monitor at the same time. The only thing abnormal thing I did for LE was to change my fan curve a little to ensure the GPU temp stayed in the 70’s. The problem I have with your advice is that it should be a LAST resort option when all others (like the FXAA mentioned about) have been considered as its likely that the other options will have a greater impact without forcing the 30fps limit - something I would find impossible to play anything other than Stardew Valley.
Also had this myself… It went away after a graphics card driver update.