Guys i was testing with the grfx settings to optimize performance with my new 4090 cause i could’nt hit my 144Hz target stable.
What i found out is actually not new since i had the same experience in Shadowlands already;
The compute setting quality severly increases the GPU-Load at certain locations with FOG/particles.
This maxed my 4090 on ultra, but with good it returns to more or less the usual load.
High is a compromise if you don’t want the pixelated artifacts around trees when looking at the fog, e.g. at the entrance portal to the new zone.
Some other things worth mentioning:
-RT shadows are VERY heavy on the CPU, turn them off at the superbloom event or when many players are around
-the renderscale seems bugged, if i go above, and even below 100%, my FPS drop although i’m at like 60-70% load, this should be purely on the GPU
-DX12 is way slower than DX11 for me… what the hell
-G-sync does not work in DX11 and it stutters if i playback a video on my 2nd screen, so i’m basically forced to use DX12 with worse performance
-i have 10-15 FPS less with DX12 in Valdrakken than DX11… with my 2070S it was the other way around, like it should be since DX12 has less CPU-overhead (that’s the whole purpose of it)
-draw distance and environmental detail are also hitting the CPU hard, that’s why i have them at 8 with a 5800X3D and a 4090… still can’t play at 10 unless i’m happy with 60 or less in Valdrakken and 100 while flying around…
-simply turning off nameplate visibillity during superbloom etc. increases FPS by 10+, that’s obvious but i wanted to mention it in case someone doesn’t know 
-lowering water quality down to high also gives around 10 FPS
Some settings are naturally situational, like if there is no water or fog, lowering those settings won’t increase FPS, but will dramatically if there is.