Hi, I saw you had an issue with the black box when you aim down sights in PubG; I had the same until I changed my graphics settings in the game. I put AA to medium and it went. Some people say removing post-processing also fixed it for them. Hope it helps, really annoyed me.

This might help regarrding your black box while aiming issue: http://forums.playbattlegrounds.com/topic/5945-big-black-pixel-square-when-aiming/?do=findComment&comment=136084

Add me, We can make counter-strike videos together. (I know Sir Xboxexppert99999 and you IRL. :D)