I am running Windows XP 64 bit with 8 Gigs of ram. The 4 sticks (same brand, different speeds) are recognized in the Windows System Properties -> General tab.
Issue is: when I start running more apps (games, Firefox, Chrome, Virtual Machines, etc) and the system gets to 4 gigs of memory used, the "You are running low on virtual memory - you should increase it", dialog bubble is displayed. When I check Process Explorer, it shows my memory usage at 3.9 gigs, although there is clearly room for all 8 in the dynamic graph. I also notice my HD starts spinning more while the system pages data out. Opening more apps does not increase my displayed memory usage and decreases the performance of my machine.
Any suggestions on how to make the machine use all 8 gigs of the memory?