2 GB ram only for windows xp boot camp?

[Yes]

I got a Mac Pro and use boot camp.
For OS X I get to use all my 9GB ram but for
Windows XP it recognizes 2GB only.

I think if I'd use Windows Vista, it would recognize all of it.

But is there any way to increase the ram usage for Windows XP?

Cheers

 

[Tallest Skil]

Search. It's 32-bit, so it can't address any more than that.

 

[Anonymous Freak]

You can force XP to use up to 3 GB by adding a switch to its startup options. I don't recall it off the top of my head for certain, but I think it's "/PAE". If you search, you should be able to find instructions on how to do it.

But, yeah. AT BEST, you will get 32-bit XP to recognize a little over 3 GB of RAM. Your options to use more RAM are to use a 64-bit OS. For Windows, this is either a 64-bit copy of Vista (If you buy the "full retail" package of Ultimate, it will come with both 32-bit and 64-bit versions in the box; although you can only use the installation code for one, you don't get to use both. If you buy an upgrade copy, it will be 32-bit only. If you buy an "OEM" copy, or a full retail copy of anything other than "Ultimate", you'll have to make sure you get the 64-bit version, as they are packaged separately,) or "Windows XP Professional x64 Edition". You probably want Vista. It was 64-bit from the start, so it has better driver support.