Hello, If you plan on using only 6 cards and not expand in the future, you can get away with mainstream boards like Asus z270-P. Otherwise, you will need mining specific boards such as Asrock H110 Btc+ or Biostar TB250 BTC PRO.
from my experience - Gigabyte H110 D3A (6 GPU), AsRock H110 btc+ (13GPU), Gigabyte Fintech, (12 GPU) Asus MiningExpert (no tested with more GPU) - all works fine with 3060TI