Best answer selected by Renseru.
nI own this TV. It won't do 1366x768. It'll do 1360x768 albeit at 30hz. Using HDMI or DVI-HDMI the only HD rez it'll do at 60HZ is 1280x720, and it's not 1:1 pixel mapping. I've been trying for years, but the only way to get even close to 1:1 pixel mapping is to run it at 30hz refresh rates... it get pretty clear and crisp at 1920x1080, but that may only be because the pixels are shrunk.
nI've come to be used to 1280x720 @ 60hz. Not as crisp as I'd like, but I've had the TV for a couple years now, it has a bad backlight bleed and maybe some dying pixels on one side, so I'm gonna give it to my kids to use with their media PC after this winter is over so I can get a 37" 1080p that will play nice with my video cards.