Ram sharing issue on g31m-s r2.0

[rtlsruru]

i have a problem im running a a ASROCK G31M-S R2.0 and i have 4gb of ram but its only showing 3.19gb usable now i know it usualy means its sharing with the onboard video but i have installed a Geforce 275GTX 896mb video card and the ram is still sharing can anyonehelp me out please