Unfortunately a low budget Sceptre 32". I wanted a 32" size screen but did not want to spend a bundle on a LCD monitor. I have a very nice 27" LCD for CAD work but it was 160% more in cost than the Sceptre. I did not find a way to manually change the TV settings or an auto-detect as you suggest. There is a PC input setting but I would have to use the DVI to VGA cable to allow that input to light up.
On my tv the way to set it up is to bring the source list up and while it is still on the screen press options or tools and then I can change each input. I changed HDMI to pc and it corrected the weird edges and colours.