Do you have the source of this test?
I saw some people talking about overclocking +1500mhz on memories of new RTXs, and now with 3060ti, but is this level of overclock sustainable?
Previous generations I was able to achieve +1000Mhz with good memories (Samsung) and totally stable, more than that become a little messy, sometimes +1100 but nothing like +1500mhz...
63Mhs with 140w is not a RX 5700 killer, more efficient ok, but not so much
my 2080supers and 3070 have been oced to +1500 and have been running fine without problems