Thanks for the reply, Reeve. I gave what you said a try, but I've still got nothing. I'm noticing in the output when I try to start X the following:
NV: could not open device /dev/nvidia0 (Input/output error)
NV: couldn't map fb (0xc0000000, 268435456M) on /dev/nvidia0 (No such de
hint: there may be a ulimit restricting the amount of
virtual memory available to XFree86. It may be a good
idea to check your startup scripts for something like
ulimit -v <number>
and either boost this value or remove the line.
I'm also attaching my XF86Config file this time, just in case that helps. Note that I've tried it with and without the section labeled "nvidia specific options" and get the same results.
I can't even get the default 'nv' drivers to work - those make the desktop always appear at 640x480, though the screen is set a higher resolution, thus resulting in a giant black border around the desktop. All I can get working is the 'vesa' drivers, which of course don't let me set a higher resolution than 800x600. Ugh.