My computer has 4 gigs also and windows reconizes 3.5. I think it is windows that does not reconize the correct amount, because if i go into the system setup it shows that I have 4 gigs. All three of us show diffrent amounts so it might have something to with the system bios version. I don't know where to get a bios update, probally from the PC vendor I guess.
Dave
Version: 67.104.27.1
Library: Frameless Advanced Modular Casework Library
0004.0201.1007.012
Windows Vista Business 32 bit
Processer: Intel Core 2 Duo CPU E8400 @ 3.00GHz
Ram: 4Gig
New Era Custom Design
www.gonewera.com