tbh, i think the 1080ti is overkill here.
the 1080ti will perform excellent in 4k, however, you would want to run that gpu with a cpu that is at minimum as strong as an i7 7700k stock. comparing the 3820 with the 7700(non-k), the 7700(non-k) has atleast 25% more performance (and 50% compared to the 7700k)
1080p@144hz pick the 1060 6gb
1440p@120hz pick the 1070 8gb