Quote:

So even with XP Prof x64 my apps won't utilize all 4g? (Namely Vanguard)

Also I've heard it can be a real headache trying to find x64 bit drivers.



The 64-bit OS would address 4G+ of RAM, but the application may not (as Daye mentioned).

Finding 64-bit drivers for OLD hardware can be a headache, but just about all current development does 64-bit drivers as well (sometimes a bit later than 32). Keep in mind also, that many system-level tools would also be required to be 64-bit (such as anti-virus/firewall software).

I guess it really depends on what hardware/software you plan on attaching to the new system.


Side Note: Vanguard has a LOT of way to go for system optimization for 32-bit (SLI and multi-processors) before they start adding >3GB and 64-bit.