Crashing in ARAM

2 games, 5+crashes.

First game i froze even before the game begun in the lobby of an ARAM game. Was playing with my mate right next to me. I restarded my PC and was thinking i will just be kicked out of the lobby (it was like 20+ seconds before the game begins), yet the game started and i was late like a couple of minutes. Then i crashed 3 times during the game. 2 times game just closed with no error message, and the last time it crashed with and system error saying something about a critical error and the application needs to be terminated emidiatly. The second game i crased 2 times during the game with the same error message. Saw some other posts about game crashing or freezing, is there something going on or its just a coincidence?