League Freezing my whole pc at 5-7 mins in game.

I have never had a problem with league prior to this and I have been a fairly active player for the last 6 years or so. About 3 or 4 days ago i joined my first match of the day and all was good until i hit about 5 1/2 mins into the game and everything froze. I tried ctrl alt delete and was able to click on task manager but it opened in the background, and this was all i was able to do. Alt-tabbing, shift tabbing, nothing worked I was stuck on a frozen league screen. I had to manually turn off my pc via power button and restart everything just to get my pc to function. It has happened to me in every game since then and I now have leaverbuster and have gotten reported tons of times for afking. I've look all over the internet and spent countless hours going through forums trying to solve the issue. I have found a few other reports of this, but the only recent ones have no responses and the others are from a few months back after the pike update. Apparently a lot of people had this problem then too, but the it was solved by the dev team. Every fix I have found has not worked for me. I am unable to give a dump file when it occurs bc the whole pc locks down. Help me please rito.