Rumor has it the 7000-series X3D chips that are coming down the line aren't going to be down-clocked relative to their non-X3D counterparts. Maybe they're undervolting or just better binned? I guess we'll find out shortly.
According to TechPowerUp, they’ve solved the heat dissipation problem for this gen in a different way:
> These would use one or two "Zen 4" chiplets with stacked 3D Vertical Cache memory. A large amount of cache memory operating at the same speed as the on-die L3 cache, is made contiguous with it and stacked on top of the region of the CCD (chiplet) that has the L3 cache, while the region with the CPU cores has structural silicon that conveys heat to the surface
