Thinking of upgrading to Vista 64 bits...

[Tirrex]

I have Vista 32 with 4GB of RAM, but the stupid OS only recognizes 2GB. I updated BIOS and tried changing settings on it, but I couldnt get any more RAM than 2GB to show on Task Manager as available to applications.

So I'm thinking of Vista home premium 64. Anyone uses a 64-bit OS or know people who uses it? I heard theres a ton of stuff that wont work. Does WoW, Photoshop, 3D Studio... stuff like that works on Vista 64? And can I use the same key I use on my Vista 32? I remember that when I bought this Windows I could just order a CD with the 64-bit version for $10. Not sure if I can just download Vista 64 and install it.