The last I got running with 9 GPU's were the Asus Z270f boards, with 2x M.2 to Pcie adapters.
But since then I have found almost no newer board that can run 9 GPUs without splitters, none of them have 7 pcie slots anymore.
So want to know about your experiences - what Regular Gaming boards have you gotten to run with 9+ GPUs?
never seen before if gaming mobo has 9 pcie

, 8 with m.2 converter, and nowdays getting less pcies
manufacture focused on m.2 slot rather than pcie, sli & crossfire getting less atention from gamer & developer they run poorly on gaming performance