Black Bars in CSGO after Creators update

I recently updated to the Creators update for Windows 10 and after that my 4:3 Black Bars was forced to streched i play on 1024x768 with a Acer KG241Q mygpu is Nvidia (GT 720 for those that even care) the streched res bothers my eyes and i feel easily distracted by it thats why i play bb