Graphics card failing?

Lately I have been experiencing random encounters where in the middle of a game or something mildly graphics intensive, output from my computer to the monitor will stop sending me anything. I at first thought it was over heating and shutting itself down, but after it happened one time, I opened my case to check the temperature or to see if any fans stopped working. Everything was still running and nothing seemed to be over heating. The computer seemed to still be running like nothing happened except I had no audio or video. I have an HDMI cable running from my graphics card to a TV I am using as a monitor. I am not sure if the fact that I am using a TV for a monitor could cause the problem, but I honestly am not sure what to do. I will re-seat the graphics card after the next time it happened and see if that helps. Until then, I ask you guys for some help.

Mobo: GIGABYTE GA-A75-UD4H
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Graphics Card: XFX Double D FX-785A-CDFC Radeon HD 7850 2GB 256-bit GDDR5
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

CPU: AMD A8-3870K Unlocked Llano 3.0GHz Socket FM1 100W Quad-Core Desktop APU
http://www.newegg.com/Product/Product.aspx?Item=N82E168...