DisplayConfig X settings for Sharp Aquos LC-32D6U?

I'm trying to use a Sharp LC-32D6U with a PowerBook G4/1.67, using a DVI-to-HDMI cable. I've found a couple of posts with suggested timing data for DisplayConfig X or SwitchRes X, but so far those have only given me a black screen. The best resolution provided by default is 1280x720, but that leaves text very blurry (which isn't a surprise, since the native resolution is 1366x768). Has anyone gotten this combination to work, or does anyone have pointers on how to go about guessing possible settings? Thanks.