Client black screens and crashes

Everytime I launch a pvp game on the client, it black-screens before crashing, and I have to wait until the game ends before I can even re-log back into the client. The only message i get is that an unexpected error has occurred on the new client, and unable to connect to pvp client on the legacy client. I've tried every single fix that Riot has posted, and run the hextech client multiple times. I'm new to this game and now I have to wait ten minutes just because it's one of the buggiest things I've ever encountered.