Problems with vesa X driver

[Stephen Powell <zlinuxman@wowway.com>]

Due to a bug in the MACH64 driver (see Debian bug report 726585 for details),
I am temporarily using the VESA X driver in Debian jessie to get graphical
support to work on my machine.  I am experiencing three problems with it.

First of all, I can only get 1024x768 resolution to work at a 60 Hz vertical
refresh rate.  That would be fine if my monitor was a modern flat screen
digital one which was designed for a 60 Hz vertical refresh rate, but it's not.
It's an old-fashioned CRT-based monitor.  Both the monitor itself, as well
as the video card, are capable of 1024x768 resolution at 85 Hz vertical refresh,
and as far as I can tell, there is a video BIOS mode for this as well.  But
the driver still uses 60 Hz.  Here is my /etc/X11/xorg.conf:

   Section "Device"
           Identifier "Default Device"
           Driver "vesa"
   EndSection
   Section "Screen"
           Identifier "Configured Screen"
           Device "Default Device"
           Monitor "Default Monitor"
           Subsection "Display"
   #
   # Note: specifying a mode name of "1024x768" eliminates interlaced modes
   # from consideration.  Interlaced modes have a mode name ending in "i".
   # For example: "1024x768i".
   #
                   Modes "1024x768"
           EndSubSection
   EndSection

The second problem is that if I switch from the graphical console back to a
text console (with Ctrl+Alt+F1, for example), then switch to the graphical
console again (with Alt+F7), the graphical screen is now very dim.  The only
way to recover is to restart the server.  (Logout of graphical screen, then
switch to text console with Alt+F1, login as root, then issue

   /etc/init.d/gdm3 stop
   deallocvt 8
   killall console-kit-daemon
   deallocvt 7
   /etc/init.d/gdm3 start

This recovers screen brightness on the graphical console, but I had better
not switch to a text console again or I'll have to go through the above
exercise all over again.

The third problem is that if my initial text video mode set at boot time
(by the vga option) is other than the default 80x25 text mode, attempting
to switch back to a text console from the graphical screen locks the system.
Obviously this driver has problems with correctly saving and restoring video
modes.  Does anyone have any ideas how to solve any of these problems?  I
have a feeling that the last two problems are bona fide bugs which will
need to be reported.  However, the first problem may be a usage issue that
I can solve with appropriate tweaks in xorg.conf.  I just need to know what
to do.  Ideas anyone?

-- 
  .''`.     Stephen Powell    
 : :'  :
 `. `'`
   `-