So, long story short, weird driver behavior with my strix 5700 xt.
Any video (even a few MB ones) is going to run the memory at 625 mhz.
Tried resetting to default in wattman, tried reinstalling the drivers (clean install), nothing helped so far.
Also tried to create a profile for mpc-hc in gaming tab, same issue (though disabling freesync and vsynch solved the tearing problem)
Default wattman setings and auto undervolt - same issue.
Win 10 1903, R7 3700x (stock, 1800mhz infinity), 32g 3600mhz ram (running at stock xmp profile), 5700 xt strix. Single 1080p freesync monitor @75hz
Weird having memory go 50c+ and 20W power usage while watching videos...