You cannot tell the difference between 16 and 32-bit in windoze because its just not there most of the time. Icons use 8-bit color for the most part, and most applications use 8 or 16-bit color for their splash screen and graphics. Most digital pictures are already compressed with Jpeg or Gif compression, which automatically cuts the number of colors in the image tremendously. You dont need 32-bit because nothing 2d on your computer requires it. Try scanning an image in as a 24-bit bitmap (make sure it contains LOTS of colors and gradients). Then switch between 32 and 16-bit. Youll see the difference.