Hello,Does anyone know if I can *upgrade* from existing 32bit to 64bit XP? Or do I have to go full new install? I can ghost my current setup, so I can experiment, but I need some info, how to change? I know that I have to install 64bit drivers afterwards, all are available, but for windows, any upgrades or something?

I am sure there are people round here more expert than me on this subject, but for a start it would be useful to know are you going from Windows XP home or professional to Windows XP x64 Professional or Windows XP home or professional to Vista 64 Best and Warm RegardsAdrian Wainer

From XP Prof 32bit to XP Prof 64bit. Thx.

No, you cannot upgrade Vista 32-Bit to Vista 64-Bit without a full reinstall.Hope this helps ;)Pat

That's all I wanted to know, thx :) In short, I won't be doing it. I don't think it's really a great advantage in case of FS9...

It'll take a few years until you will be able to unleash the full potential of a 64Bit OS anyway. Right now, there are "some" performance improvements over 32Bit, but they're generally in the sub-1% range.More techically: An application has to be compiled in 64Bit to really show some additional performance (ie. make use of the additional address space), but it's far to say that 64Bit apps are twice as fast as 32Bit apps.The only reason right now to go with a 64Bit OS is to break the 4GB RAM limit and since hardly any customer app makes full use of 4GB anyway and additionally is not optimized/compiled in 64Bit, there is no reason to switch, as far as I am concerned.Hope this helps,Pat