Softly softly catchee gamer monkey
Halo fans will have to upgrade their computer if they want to follow Master Chief's adventures on the PC.
Microsoft has announced that the PC version of Halo 2 will only work on the new version of Windows called Vista.
The decision could make it expensive for many to play the game if they have to buy the new version of Windows and extra hardware for their PC.
Microsoft has given no definite release date for Vista but it is expected to be available by the end of 2006.