Welcome our new sufferer, DrDisrespect from twitch. There are two links here where he is trying to fix the issue with graphics settings. Everything was great the previous day, then it went jaggy and crap the next.
The youtube video ends when he says he fixed it. He didn't. If you want to find out more about this issue. watch the full stream on twitch on his page. The stream title is : "Nothin but wins w/ NICKMERCS | @DrDisrespect ". It's a 7 hour long stream. There is hope now because he is a well known twitch streamer. However, he might just buy a whole new rig for his next stream and from what we know, it solves the issue temporarily.
Skip to 6.58 for the youtube video.