Not doubting you but looking at your system specs of a Asus Z97-P, GTX 970, Samsung 840 pro I have to admit that I find it hard to believe you haven't updated any drivers since you got that hardware.
That's because they're not meant to be a viable alternative to a PC, like I said if you're already running Windows then a full blown Steam Machine probably ain't for you.
The full blown Steam Machines are intended to create a console-like experience on the PC platform, Valve don't want to convert PC users into Steam Machine users as they're probably already customers of Valve, they want to convert console gamers as that increases how many people use Steam, increases their potential revenue.
Indeed, like I said if you're already running Windows then a full blown Steam Machine probably ain't for you, if your happy using Windows then SteamOS and Steam machines are probably worse than what you're using now, you would probably be happy with the Steam Link if your PC is in another room, or maybe just a Steam Controller.