I want to use my 42" LCD 1080p TV as my monitor for my computer. For gaming, internet browing blah blah.. basically use it as my main monitor. I'm concerned with if it's going to be too much stress on my system to push the video to that big of a monitor. Or if it's any more stress than a 22" monitor. I usually run my games highest res possible.
I'm almost positive the screen resolution is the main stress for your graphics card, not the size of the screen. So you should be fine with a 20" or a 42".
42" is going to be tough to game on though, really big. I run on a 28" and it's great but I don't think I'd be happy with something bigger for gaming. Since computer games you sit close, it's a lot to take in.
I've thought the same thing, I just have never tested nor have I ever seen any thing relating to it. I just recently upgraded my TV to a 55" 3D LED and I have been thinking about hooking up my tv to my computer try games out on it. I just wish I knew of someway to test it. Last thing I want is to kill my Vid Card.