Yesterday and today I have spent quite a lot of time playing around with Lilliput and DWW-700H 7" wide screens. It appears to be a pain in the <censored> to get them working with 800x480, which is their native resolution.
I have used (among other sources) this page:
http://www.macvroom.com/node/36 but when I use the parameters listed, I do not get 800x480, but rather 800x500 (using native resolution and cutting of the remaining 20 pixels at the top or bottom depending on the v position in the OSD).
Any idea about how to get true 800x480 for these screens?