AMD RADEON RX 7900 XTX VS RTX 4080 OPTIONS

In addition they downgraded their PSU advice to 650 W for each cards. Was 1000W over the 6900. I think I would truly feel a tad close on 650 W even enabling for your high quality device with the ability to source in excess of rated for brief moments. 650 would surely be way to shut for any 13900K program, what do they know that I dont? Radeon card