Same here, actually installed it the other day having never played fo76…
it played like shit (<15fps) with barely any hardware usage (GPU doing nothing, 14% CPU utilization) . Found out it needs to be played in full screen mode (on AMD cards at least) to actually utilize GPU, confirmed that was the issue and uninstalled it.
But the game is apparently good if you can get it to work or look past some dumb shit like this.
You can also pierce your ear drum with that thing (if something hits your elbow at the wrong moment) …about 12 years later and it’s almost as good as it was before it happened 😎😵