VBEHz 2.23
==========

A German documentation is no longer included to save time (and work).

This program increases the refresh rate on video boards supporting VBE 3.0.
To install it type "vbehz" (without quotes).



CAUTION: My program does not check, if your monitor supports the
         frequencies, set in VBEHZ.COM that's your job
         (see table in VBEHZCFG.TXT).
         I WILL NOT BE LIABLE FOR ANY DAMAGE.
         (newer monitors, however, protect themselves by switching off)
For the default settings your monitor needs at least 82 kHz horizontal
scan frequency.



Currently supported VESA resolutions:

  640 x  400, graphics
  640 x  480, graphics
  800 x  600, graphics
 1024 x  768, graphics
 1152 x  864, graphics
 1280 x 1024, graphics
 1600 x 1200, graphics
  512 x  384, graphics, double scanned, else NVIDIA Chips can't handle it
  400 x  300, graphics, double scanned
  320 x  240, graphics, double scanned
  320 x  200, graphics, double scanned (VESA only, no mode 13h or similar)
   80 x   60, text,     may require loading RIVAFIX.COM first on NVIDIA Chips
  132 x   25, text,     may require loading RIVAFIX.COM first on NVIDIA Chips
  132 x   43, text,     may require loading RIVAFIX.COM first on NVIDIA Chips
  132 x   50, text,     may require loading RIVAFIX.COM first on NVIDIA Chips
  132 x   60, text,     may require loading RIVAFIX.COM first on NVIDIA Chips


Currently supported VGA resolutions
(by additional programs that may not work on some cards, see VGA.TXT):

  640 x  480, graphics (mode 12h)
  320 x  200, graphics (mode 13h)



The more resolutions and colour depths your hard-/software supports,
the more memory will be used by VBEHz (580-1100 Bytes).

To see which modes your BIOS or VESA driver supports, run
MODELIST.COM |more



If VBEHz is resident and you run VBEHZ.COM again, the resident part will be
diabled until you run VBEHZ.COM once more. This allows you to load VBEHz
in your AUTOEXEC.BAT and disable it later for one or more programs.
VBEHz can be forced to get resident again if started with "/r"
(vbehz /r), this can be useful if you reconfigured it and don't
want to reboot (or close the DOS-Box under Windows).

En-/Disabling is done by calling INT 10h with AX=4FBEh, if VBEHz switches
to disabled, it returns AL=01h, if switches to enabled, it returns AL=02h.

If you use VBEHz within .BAT-Files, it will return errorlevel 2 for
enabled and 1 for disabled. If it is run for the first time, it will not
return an errorlevel (or errorlevel 0).



Notes:
 - The BIOS of your video board may not support all of these modes,
   and my program will not add the missing modes.
 - There may be problems with programs using DOS4GW, but I don't
   know why.
   If DOS/4GW is a seperate EXE-file you should replace it with
   DOS/32A, PMODE/W oder CauseWay.


