Chess King is compatible with pretty much all Windows systems, from of course Windows XP all the way to the most modern Windows systems.
If the computer is super powerful, it can take full advantage of Chess King Pro for multiple cores. For very weak and old PC's Standard Chess King is fine (and Pro would not be recommended, it's a very powerful engine!)
Currently, Chess King can also be used on Macs using the visualization software VMWare Fusion.
Chess King is directly installable on Windows PC only. However as you can read at the end of this article, you can use Chess King quite well on a Mac via the emulator VMWare Fusion. The functionalities of Chess King in emulation mode are exactly as original and the speed is excellent given that Chess King contains the strongest engine available Houdini 2, and that Macs now use the same Intel chips as Windows.
You will also find lots of info on the Chess King TUTORIAL PAGE.