Computer Crashing When Loading

well, champ select and all that is fine, but when we start loading my screen flashes the loading screen and black off and on, and then sometimes it blue screens and other times it just restarts my computer. there was one time tho, i alt+tab quickly as the loading screen was about to appear and it did the black screen flash thing, but it didnt crash my pc, but when i clicked the league icon on the task bar, it showed the loading screen, then did the black screen flashing again and my computer restarted itself again. i dont know if this has to do with the offline thig, but every time i opened the client again, it said the offline thing and i keep having to delete that line of code that you said would temp fix the problem. hopefully you guys can get back to me

UPDATE:

im am editing this to say that my computer is doing this even in game, im am playiing norms with a friend and they didnt remake and i tried to get back in the game after the loading screen and i crashed then i tried to join mid game again and i crashed, so i would like to play my game and if anyone at riot knows if its a so called common thing, can you put out a post about what other things i need to delete :P

UPDATE:

it might have been caused by shadowplay because i turned it off and i was able to get into the practice too fine, but i would prefer if the leaver buster wouldnt give me a matchmaking penalty for something that i cant control