How much beyond 3GB RAM the system could recognize in a 32bit OS is determine by the motherboard. Newer chipset is able to to auto disable Executing Bits and enable PAE (Physical Address Extension) to allow the OS to recognize more than the physical limit.
If you have 4GB+ or more memory, 64bit OS is definitely a must, otherwise anything over 3.5GB will be useless. Most new package system comes with Vista 64 already due to 4GB of RAM.
So far, Vista 64 has been good, only that some major applications such as Simply Accounting 2008 still refuse to work with it.
Philip |