Quote:Original post by daviangel You realize you won't be able to use all 4GB with a 32bit OS so I don't recommend that much mem unless you running 64bit OS.
Why not?
Because a 32-bit OS can only has roughly 4GB of address space.. which is used by other devices. So once you throw in the 768MB from the GTX (or 1.5GB SLI) you'll only be able to see/use 2.5-3GB.
Quote:Original post by daviangel You realize you won't be able to use all 4GB 3GB in a single process with a 32bit OS so I don't recommend that much mem unless you running 64bit OS.
Fixed. The OS will reserve the upper 1GB of the address space (actually it normally grabs the upper 2GB, but you can change that in boot.ini), but on CPUs with Page Address Extensions (PAE, which I think all modern CPUs have, IIRC it was introduced with the Pentium Pro) it can access in total up to 36GB.
EDIT: Ok, forgot to include devices that eat into that address space as Saruman pointed out.
"Voilà! In view, a humble vaudevillian veteran, cast vicariously as both victim and villain by the vicissitudes of Fate. This visage, no mere veneer of vanity, is a vestige of the vox populi, now vacant, vanished. However, this valorous visitation of a bygone vexation stands vivified, and has vowed to vanquish these venal and virulent vermin vanguarding vice and vouchsafing the violently vicious and voracious violation of volition. The only verdict is vengeance; a vendetta held as a votive, not in vain, for the value and veracity of such shall one day vindicate the vigilant and the virtuous. Verily, this vichyssoise of verbiage veers most verbose, so let me simply add that it's my very good honor to meet you and you may call me V.".....V
Quote:Original post by daviangel You realize you won't be able to use all 4GB with a 32bit OS so I don't recommend that much mem unless you running 64bit OS.
Why not?
Because a 32-bit OS can only has roughly 4GB of address space.. which is used by other devices. So once you throw in the 768MB from the GTX (or 1.5GB SLI) you'll only be able to see/use 2.5-3GB.
With two graphics cards that each have 512+ MB of RAM, you're in real trouble on 32 bits, because you need to both map (and backing store!) all that RAM, and you need space for the kernel, and you need space for your application. Running the 64-bit version of Vista isn't out of the question at that point!
With 4 GB of RAM, the entire system can use it, but each process can only use about 2 GB of RAM (assuming another 1 GB goes away because of the graphics cards, especially if using OpenGL drivers).
