I recently received a home-built computer, and it has these four NVidia "SLI Compatible" 16GB sticks. They look almost exactly like ram sticks, except they are shaped slightly different. When plugged into my motherboard, they each give me 1GB of regular ram, but I believe that they do more than that. Can anyone tell me what these are used for or what they improve in the computer? Thanks so much to anyone who can answer this question!