I've had my PC for just over a month now but the whole time I've had it, on certain games after 5 minutes or less than opening it, the screen goes blank and i get 1 long beep followed by 3 short ones from the mobo... I have an ASUS Sabretooth 990fx mobo, Sparkle GTX 660 graphics card and an AMD FX 8350 cpu. I looked up the beep code and it means that there is a memory failure with my graphics card, I have reseated it on my mobo and RAM and even reinstalled my graphics drivers, it's just really confusing me because it works on games such as Arma 2, Arma 3, Killing floor but not with games such as Defiance, Loadout and TF2... So what could be wrong??