DH67CL HAS 1.5 GB BUILT IN GRAPHICS
1. The motherboard doesn't have inbuilt graphics.
2. The processor has inbuilt HD 2000 graphics with 64MB dedicated video RAM. the remaining are taken from your RAM.
Memory doesn't really matter in graphics hungry games. Are you an Indian or Pakistani? They think that the Graphical Memory is what matters in Gaming and so, buy cheap 1GB cards and thinks that they'll perform better than costlier 512MBs...