Number 4 is the key here. The application or game itself be written to take advantage of what your 64-bit CPU has to offer. Without this, there isn’t going to be any benefit in game performance on an x64 platform. There is a difference between just being compatible with WinXP Pro x64 Edition and actually utilizing what the 64-bit CPU can do for a game. Therefore, we are still waiting for a game that can fully take advantage of a 64-bit CPU. It seems as if the main problem for Windows XP Pro x64 Edition is the availability of 64-bit drivers, applications and games.
Windows x64 Edition Gaming
HardOCP has written up an article looking at the current state of gaming on the newly released 64-bit version of Windows XP. They did find that Splinter Cell refused to play in the new version of Windows…