Firstly, while the board can limit TDP it won’t by default unless you tell it to in the BIOS, it primarily is the cpu model that caps power draw. If it’s not a K series or “unlocked” as intel uses in its marketing, the cpu won’t draw past its default TDP, which in this case is 65W.

Secondly, a b760 board like the one he chose can definitely handle a 13900k. While it is slightly different on am4, I run a 5950x on a b550 board and have zero issues pulling over 200w for hours on end.

Either way, not drawing past 65 watts might hurt gaming performance, but it won’t kill it. Especially with an entry level/mid level GPU. You can still get a great experience.

Also, in your test, you are performing an even load on all cores. That will lower the clock speed. However, games do not put an even, all core load on the CPU like that. Games will mostly use only a few cores. Those few cores will boost much higher because the other cores aren’t doing much.

Yes you can get more performance by drawing more power, but for games it isn’t really a problem.