bliblubli,
Using this blender 2.79 benchmark with my 2x rtx2070. Here is the link The new Cycles CPU 2.79 Benchmark. Your build is actually slower.
Latest build 2.80 (tiles 256x256): 51.32
your RTX build: 57.16
Without denoiser:
Latest build 2.80 (tiles 256x256): 49.63
your RTX build: 38.77
The problem is that your RTX build when automatically using small tiles has very poor denoiser performance. Can you fix it so I can enter manually my own tile size when I am using the denoiser.