Auto LLC will cause slight voltage deviations, too aggressive and the voltage rises, too weak and it droops.
To be fair, I don't see the worry with those temperatures, my 1920x was getting up to around 82 degrees using an original EK water block with 480 & 240mm radiators cooling it. I've since replaced that block with the newer redesigned version that actually has full die coverage which has dropped my peak temperatures to 70 degrees. These temperatures are a bit unrealistic as prime 95 small FFT seems to really cook this processor, encoding and other benchmarks are around 10 degrees lower. Another cause for the high temps is the overclock at 3.975GHz / 1.325V.
I've seen others with the noctua cooler and old asetek aio's getting better temperatures than I do using similar voltages so I do wonder if my cpu has some trouble dissipating heat from the dies through the IHS to the waterblock.