PC version Fans have made a PC version. Some are still early, so read the project page first.
Fans took Star Wars: Episode 3 - Revenge of the Sith with Multiplayer apart and rebuilt it so it runs natively on a computer, often with widescreen, higher frame rates and mods. Here is the project we know about:
Unofficial native Windows port of Star Wars: Episode III - Revenge of the Sith (Xbox). Bring your own copy.