Just saw this and honestly you really gotta be careful with that chip. The 14900K pulls insane current and if your vrm cooling isnt top tier youll see serious throttling during long 4k exports. I would suggest looking at the ASRock Z790 Taichi LGA 1700 E-ATX instead of the super expensive asus options. It has a massive 24 phase power delivery that stays way cooler than the strix boards under sustained load. Just make sure you update the bios immediately and check the intel default power limits because motherboard vendors love to crank the wattage out of the box which is what leads to those stability issues people talk about. Also you might want to consider grabbing a Thermal Grizzly Intel 13th/14th Gen Contact Frame to keep the ihs flat. Without it your temps could be 10 degrees higher regardless of which board you pick... its just cheap insurance for a build this expensive.

In my experience, you cant cut corners with the 14900K power draw. I've tried many setups over the years and for your budget, the MSI MEG Z790 ACE LGA 1700 E-ATX is the safest bet for stability. It has massive cooling for the power delivery. Vital for editing. The ASUS ROG Maximus Z790 Hero DDR5 ATX is solid too, but MSI feels more robust for heavy workloads.

TL;DR: Dont blow your whole budget on the mobo. High-end mid-range boards like the Gigabyte Z790 AORUS Master X E-ATX provide the same stability as $700 flagships for heavy 4K editing. Honestly, you're hitting diminishing returns fast once you cross that $450 mark. Most of those Extreme or Godlike boards are built for liquid nitrogen overclocking, which isnt what you need for a stable workstation. For a 14900K, you just need a board with a beefy VRM and decent heatsinks... basically anything above a certain power phase count will do. The Gigabyte Z790 AORUS Master X E-ATX is probably the best value for your specific chip. It has 20+1+2 power stages, which is frankly overkill for a stock 14900K, but it ensures the board runs cool while you're rendering. If you prefer the ASUS BIOS, the ASUS ROG Strix Z790-E Gaming WiFi II LGA 1700 is another solid choice that saves you a few hundred bucks over the Hero. It still has the PCIe 5.0 slots and plenty of USB headers for your peripherals. Better off putting that extra cash into a massive cooler like the ARCTIC Liquid Freezer III 360 AIO instead. That is what's actually gonna keep your 14900K from thermal throttling during long export sessions. The mobo's job is just to deliver power cleanly, and these mid-tier options do that perfectly fine.