Go into the properties section of display, find the default setting or basic VGA setting, accept it and save before leaving. Shutdown system, connect DVI cable, then power-UP, hopefully, if should see new hardware and proceed foward. If not, does the Sony have any CD/floppy with it? it may contain the drivers to better accept the Sony LCD/monitors display ranges, etc.. AND/OR under 5200 setting, make sure you select what display is now 1, or 2 if more than one, if only one, then the other is OFF or not active, though it should do this automatically. 5200 display setting can be updated, so get the latest either from the video card maker or Nvida support website.

enjoy -----Willy Happy