Whenever I try to launch a game such as DOTA 2, DayZ, or any game in my Steam library, they just launch and instantly close/crash. I have re-installed steam and a few games, and none of them work. This is just a problem with steam as I can still play BF4 and Minecraft just fine. I haven't changed anything with my computer recently so I'm not sure what is causing this. Any help will be appreciated.
running Windows 8.1 Pro