<snip re: trouble getting video set up in X>
try using xf86config, of xf86cfg to reconfigure X, and see what happens.
xf86config changes my old X3 config file, and xf86cfg messes up my screen.
It spews out some messages that I cannot see because the screen goes into
graphics mode, then it draws an image of a monitor, a videocard, a computer,
a keyboard, and a mouse, in addition to the outlines of a few boxes and some
1 pixel wide lines at the top of the screen, with a number of random pixels
to round out the mix. It's a little amusing in a way... if I start X, at the
top of the screen I see two miniature images of that screen at the top.