Game Crashes: Inquisiton, GTA, Shadow of Mordor.

Greetings, over the past 24 hours or so my computer has gone through some issues with windows not loading, once I got those fixed my games don't wish to run anymore.

Here's the process to force a crash: Launch a game, start up story mode, run around for 3 minutes. At this point the game will stop, the screen will go black, and the monitor will no longer read a connection. I'm thinking it's a graphics card issue.

What I've done: so far I've tried rolling back the driver and underclocking it. Underclocking the card seems to be the only thing that works but I haven't tested it beyond 10 minutes in Shadow of Mordor. I also don't want to have to run my card underclocked for any game I play because I enjoy maxing out the settings as much as possible. I have also tried toning down the graphics thinking it might be a specific setting. I did this with GTA and just turned up individual options one by one, but nothing seemed isolated and I still crashed. Note: I don't seem to have issues with every game, Dark Souls 2 SotFS seemed to work just fine, I'd have to test that further though.

I'm wondering if anybody knows of any solutions, if it's a graphics card failure though, do you know of any replacement policy that Newegg has? I purchased the card in early-mid January and I don't think I've run it through it's full life cycle after only 3 months of ownership.

System: Windows 8.1 Pro (6.3, Build 9600) AMD FX-6300 6-core @ 3.5 ghz 16 gb DDR3 RAM Nvidia GeForce GTX 760 4 gb