The new ASUS ROG Thor 1000W Platinum II PSU for example has a 12-pin PCIe cable bundled and can "pipe up to 600W of power to PCIe Gen 5.0 graphics cards" of the future.

If you don't have or won't be buying NVIDIA's new flagship GeForce RTX 3090 Ti graphics card, the new 16-pin PCIe 5.0 power cable is kinda useless for now.

The cable is set to replace the severely outdated 6-pin and 8-pin power connectors that weren’t designed with 500W or higher GPUs in mind. A card with three 8-pin connectors supports 3x150W ...