Aurora-R6, issues with my games graphics

Hello, 

Sorry if this seems like an obvious fix, I'm fairly ignorant with computers. Anyways, I've had my Aurora R6 for about 1.5 years with zero issues. I was cleaning today and opened it up to clean out any dust (I've done this about 4 or so times before without any issues) and when I put it back together everything worked as normal. I turn on overwatch and the settings were adjusted to low graphics and some very poor resolution that was well under what I normally play at. So I try to adjust it in the options of the game and it wasn't working. So I check destiny to see if it was only an issue with overwatch and for some reason it says that Destiny 2 isn't even installed. I played both games only yesterday. So then I turn on Monster Hunters and the graphics was painful and it was so laggy that I could barely work it. Idk what to do or what I did, please help.