I have a new PC, using the second gen intel i7, and the sandy bridge chipset. I can connect my monitor's HDMI-cable to either the builtin graphical connector (the one powered by the CPU, one of the chipset features), or a cheap Nvidia card which I happen to have. The picture quality is very different: the builtin graphics gives me very crisp and clear picture with bright colours, and the Nvidia card gives me a bit blurrier, darker picture. Same monitor, same cable, different HDMI providers.