How to modify xorg.conf from command line in rescue console (F7)

[Bo Berglund]

On Mon, 03 Sep 2007 08:55:15 +0930, Tim <ignored_mailbox at yahoo.com.au>
wrote:

>On Sun, 2007-09-02 at 20:40 +0200, Bo Berglund wrote:
>> At this time I should have checked that all was well by logging off
>> and logging on as the new account and also by restarting Fedore, but
>> instead I accepted the 178 updates...
>> 
>> After several hours of downloading and installing Fedora asked to
>> restart and I did so.
>> 
>> Unhappily, the start was no good. Now when the login screen should
>> appear in 16 bit color mode as per my changes in xorg.conf for some
>> reason it starts up in 24 bit bode and the screen is unintelligible.
>> :-( 
>
>You might want to a "system-config-display --reconfig" now, to start
>configuring X from afresh.  The updates *may* have resolved your
>previous graphics problem.
>

But since Fedora won't start up how can I even do anything like what
you suggest?
And if it starts up in a usable mode then I don't need it...

Anyway, I have tried 2 times more to start over from scratch:

2nd install attempt
===================
1) New virtual disk and start install from DVD image with all the
switches needed to get the installer screen working.

2) At the end after the reboot starts I capture the install DVD again
and boot to the rescue console.

3) There I edit etc/X11/xorg.conf to change 24 to 16 as depths
4) I also edit boot/grub/grub.conf and add the kernel parameters I
have used to get the installer running (vesa i8042.noloop
psmouse.proto=imps clock=pit vga=771)

5) Then I boot only to discover that Fedora is panicking because some
CRC error has emerged, probably you are not allowed to edit grub.conf
in this step???

3rd install attempt
===================
This is where I am now...
1) Again a new virtual disk and install Fedora using the switches etc
I know work.

2) At the final reboot I switch off the virtual machine and save the
changes on my undo disk to the main virtual disk. So now I have a
system I can experiment with where the main install has been done but
the first boot is yet to be performed.

3) Then I started it up again and just changed the parameters for the
kernel as stated above, no file editing from the rescue console.

4) I have gotten as far as seeing a black screen with the X mouse
cursor for a while, then it goes totally blank and the cursor
disappears. After some time there are 3-4 times a sudden jerk in the
screen and a cursor appears for a fraction of a second and is gone
again. Then just a black screen....

5) Then I switched off and reverted to the undo disk again and this
time I used the rescue function on the DVD to get me to the point
where I can edit xorg.conf. Changed 24 to 16 and accepted the changes,
and restarted.

But the exact same thing happened, and after a while I am now staring
at a black screen...

I have run out of ideas....

Strangely on my very first install attempt yesterday I actually
managed to get into Fedora but when all the updates were installed and
I restarted the screen was totally garbled and I could get nowhere.

Today after carefully checking my steps I get to the black screen with
nothing showing. Too bad.

I have saved the virtual hard disk from yesterday (I did not use undo
disks then) so I could start that up again if need be. Maybe I am
actually further along in that attempt, just a matter of getting X to
not use 24 bit color depth. Mind you, I have an xorg.conf file there
that is set for 16 bits...

Bo Berglund