my config is C2D 8400, 2x2gb 800MHz ram, Asus P5Q-Pro, 500gb HDD, XFX 8600Gt,...
the problem is that my vista ultimate 64bit is showing only 3gb, i even tried Win7 64bit, but still same. there is something called "Memory Re-mapping" in the bios. tried enabling and disabling it, but no use...