I can confirm what the article states. I have 4gigs of ram along with 2 8800 640MB GTS cards. 32-bit operating systems allow me ~2.75GB of system memory. I run 64-bit Vista Premium for this very reason, and the full 4 gigs are definitely available. So far I've had no driver problems and games generally run fine.
Here's the official MS article on the 4GB issue:http://support.microsoft.com/kb/929605/en-us
Back when the Athlon 64 was just coming out, the websites downplayed that we'd need 64-bit anytime soon, as desktops wouldn't need more than 4gigs of ram for the foreseeable future. It's funny how they missed this little issue; you can hit the 4gb barrier without having more than 4gb of main memory.
Why do I have 4gigs you ask? I had two, but I was experiencing disc swapping at the start of missions in Company of Heroes. It turns out that at max settings, the game alone uses 1.5 gigs of memory at the beginning of each map. This is not a rumor I've heard, this is what I've observed with Windows Task manager. Interestingly, this same game is currently hitting the 32-bit limit as we speak since the DX 10 version was released. Windows apparently allocates 2gigs per program, and under DX10 with the highest settings, Company of Heroes can surpass this.
From the Company of Heroes DX10 (“d3d10”) FAQ and Benchmarking Guide ( http://forums.relicnews.com/showthread.php?t=150531
):Q. Can I do anything to prevent CoH from running out of memory when playing certain maps at very high resolutions and anti-aliasing settings?A. No, you must lower your display settings. By default Vista 32 gives each application two gigabytes of virtual address space. You can look up how to change this to three gigabytes, use Vista 64, try the -notriplebuffer or -novsync command line parameters, or try newer display drivers when they are available.Running at very high resolutions and anti aliasing settings
Due to the limited address space of Vista 32 if trying to run at very high resolutions and/or anti aliasing settings the driver may consume so much virtual address space the application crashes. Running with -novsync for performance testing will disable triple buffering to recover a tiny bit of memory, but the best solution is to run Vista 32 set to give applications three gigabytes of virtual address space or to just run Vista 64 which gives all 32bit applications a full four gigabytes.This comment was edited on Jun 4, 00:59.