My original desire was to write a 16bpp fade routine so I could fade my screen to black. At first, this seemed like a trivial task. My first attempt took 17 seconds to fade a 640x480 screen to black, running on a pentium 100. Not long after seeing how long it took to fade my screen did I realize that a fade to black in the high color modes is simply a special case of the more general effect of alpha blending. In this article I will take you through the optimization process I went through in my search for the fastest possible alpha blending routine. I will start with the basic equation and end with my MMX version of alpha blending.