Take each failure and google for ideas.
So quick rundown: I go to play some Chivalry: Medieval Warfare which was working fine the other day. It prepares to launch through Steam, then pops up with "CMW.exe has stopped working". The game crashed. Same thing has happened respectively to Metal Gear: Ground Zeroes and Titanfall but some of my other games like Awesomenauts and Dota 2 run perfectly. Haven't downloaded anything at all other than driver or windows updates.
I did what I normally do and verified files, updated windows and drivers, uninstalled reinstalled, ran my Anti-virus software, No dice. All of these games have worked despite having a dated OS, but below are my current specs and driver. Hopefully you guys can offer some help.
Specs:
Operating System: Windows Vista Business
Processor: AMD FX(tm)-4300 Quad-Core
Memory: 8172MB RAM
DirectX Version: DirectX 11
Driver: NVIDIA GeForce GTX 770

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