System Shared video memory


Sep 1, 2011
I have an rather old graphics card, 9800GTX+ with only 512MB of DDR3 video memory. I found this is limiting me in a lot of the games. Today I have just received by additional 8GB system RAM, making my system with 12GB RAM in total.(mainly for VMs) And I noticed in the nvidia control panel, its listing that I have 4G of total graphics memory, and 3.5G of system shared memory.

My question is, is this 3.5G of system shared memory activated on default? Most games these days require over 512MB of video I want to make sure that my graphics card can actually access my system RAM when it runs out of its own(Which most of the time they do run out). Or is it designed that if there is a dedicated graphics card plugged in, only the dedicated video memory will be used?