Hang tightly some games!

Don't remember when exactly it started, but I remember that before such was not. One day, all of a sudden started hovering in the games.
For example, in Garry's Mod if you press Alt+Tab, the game will crash tightly. Sometimes it hangs on exit, but this rarely happens.
Or, for example, in Medieval II: Total War if you try to exit, the game also hangs tightly. If you click the Single player, then the game will crash. Sometimes it's just not even launched at startup. In the gameplay no stuttering no.
Sometimes hangs CS:GO, if you press alt+tab, but that rarely happens.
These lockups only happen in certain games. For example, in Battlefield 4, this is not Fallout 4, this is not.
I don't understand what the problem is, after all, before such was not.