Horrible FREEZING with the in-game client, no control over Windows Desktop function by blackscreen

Recently I've experienced two awful freezes with patch 6.8. I haven't seen this kind of freezing before. The game stops working, freezing the screen while playing and doesn't become unfrozen even after waiting for 3 minutes, music still playing. I tried to tab out in order to restart the in-game client but nothing worked, the LoL window just remained open frozen. I even tried to CTRL+ALT+DEL to open task manager and close the client but even while still having access to my Taskbar the client window just black screened with the music still playing, still denying me control over the desktop functions.

I had to do a pseudo Windows restart to close the in-game client BOTH times and reboot the client from there. It took a total 10 minutes to get this problem sorted out first time around, and 7 minutes the second time,** so now I have a LeaverBuster punishment due to the freezing**. Has anyone else had this problem yet at all?