I did some runs on 117 vs 127 and compared the scores. What I saw was a difference of minimum 11 points and a maximum of 31 Points on 8k optimized in favor of 127% setting. So the power setting kinda works. I'm saying kinda because you don't gain much. Still, it is there, but I think that the BIOS can be improved to limit near 127% as "advertised".
I will continue working with support and ask them for a copy of the slave bios as I believe it is not a problem with the card physically but with the BIOS.
On 1080p Extreme, it stays at 2100MHz and never hits the power limit btw.