From: lahtonen@utu.fi   
      
   Jim Leonard wrote:   
   > Jyrki Lahtonen wrote:   
   >> I'm out of my depth here, but I'm having similar troubles with   
   >> my new BenQ flat monitor and ASUS graphics card. They (don't know which   
   >> is to blame) won't give me modeX (320x240 256 colors) even though the   
   >> salesperson promised 100 per cent VGA compatible.   
   >   
   > Most likely the monitor's fault.  Hook up a real CRT to make sure.   
   >   
      
   Alas that didn't help (now that I finally had the time to try it out   
   properly).   
      
   To get a better idea what goes wrong I ran my code in the DPMI debugger.   
   The way my subroutine (cope/pasted from some web source) switches to   
   modeX appears to be that it first calls a BIOS interrupt $10 service   
   to switch to to regular mode $13 (320x200x256) and then starts tweaking   
   certain registers on the VGA card. The test run within the debugger   
   showed that this call to interrupt $10 does the damage: the screen turns   
   all black and the system hangs. Switching back to WinXP quickly follows   
   with an error message along the lines " the NT virtual DOS machine   
   encounterd an illegal instruction..."   
      
   Any ideas? Has the BIOS interrupt service $10 been discontinued for some   
   reason? This problem doesn't appear on the othe WinXP PC that I have   
   access to.   
      
   Cheers,   
      
   Jyrki   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)