I have been developing a wx.python application.  at some point  i need to create a fullscreen, no taskbar, etc. wx.Frame  which has exactly  the size of the screen and display in it a bimap which has exactly the dimensions of the screen, so one pixel of the bitmap equals exactly  one pixel of the screen.
everything has been working fine (on dvi/vga/hdmi  monitors) up to the time when i pluged in displayport monitor. 
the monitor is detected by wxwidgets to be lower  resolution than it actually  is, so the bitmap goes off the screen. EDID still  detects valid resolution so it is for sure  wxwidgets related issue.
 when i use wx.DisplaySize - it returns lower resolution than is actually  set. i also tried to create the bitmap according to the wx.DisplaySize()  output  but then, as expected, when i try to light up one pixel, its neighbours are changed too. (some sort of scalling occurs).
similar issue  occurs when i plug a projector. 
have  any of you had simmilar symptomes?  how to deal with it?
Correct EDID values does not necessarily mean that the system is running it in that display mode.  Have you checked the system's display properties or screen resolution properties to ensure that the system is driving the display at its full resolution?  Your symptoms sound to me like it is running at a lower resolution and the display is stretching it to fill the full screen.
weird scalling on displayport monitors in wx.python