I have 4 gigs of OCZ Plat in my Asus A8NSli Deluxe MOBO. I also just installed Vista 64bit to take advantage of 4 gigs or ram. However, after installing the 64bit OS it still just recognizes 3 gigs. I then checked my BIOS settings and it tells me that i have 4 gigs installed but only 3 gigs are usable. Whats up?