League client black-screening when entering a game lobby.

So i just got into a ranked game (the banning screen) and my client black-screened... i could hear the banning taking place, but couldn't see or click anything. I unwillingly dodged and got a lost in promo game plus the 5 min ban. This didn't bother me to much, but am reporting it so it doesn't happen to a diamond or challenger play in their promos.

1. press play, solo/duo, started game
2. i was playing with a friend (i don't know if this helps)
3. joined game
4. screen black (this happened to only once)