not worse, but not better
i added your settings for the AGP, and something new happened : now, thereis no more blank screen...
there is the standart command line with a superb black background, and at least 8 colors!!!
i tried startx,; and it shows something strange :
(EE) NVIDIA(0): Failed to initialize the NVIDIA kernel module!
(EE) NVIDIA(0): ***Aborting***
(EE) Screen(s): found but none have a usable configuration.
Fatal Server Error:
no screens found
XIO: Fatal IO error 104 (connection reset by peer) on X server ":0.0"
after 0 requests (0 known processed) with 0 events remaining
I joined the copy of my XFree log here