That is very odd. I get 17733 Timespy CPU score with only a PBO+curve optimizer overclock (SMT disabled) running 1800 fclk, and it is pretty hot in here (water just over 28°C). I have the same motherboard and I even have a -0.05V offset on the CPU voltage.
AMD Ryzen 9 5950X, NVIDIA GeForce RTX 3090 x 1, 32768 MB, 64-bit Windows 10}www.3dmark.com
Maybe compare scores with an 1800 fclk?
I assume you have this power management stuff disabled too?
Advanced\AMD CBS\NBIO Common Options\SMU Common Options
DF Cstates: Disabled
Fixed SOC Pstate: P0
CPPC Preferred Cores: Enabled
Edit: I don't think it has anything to do with APBDIS, setting it back to auto didn't reduce my scores at all. Very confusing!
Tried it, my score moved a little, but not much. Still in the 16 000 pts.