For months I've had no problem connecting my laptop to my HDTV to view streaming internet content. Now, for unknown reasons, when I connect the laptop one or more of several problems occur: first, the monitor on the PC goes black (although the desktop appears on the TV); or the monitor goes black and I can see only the desktop background, but no icons, and in either case I cannot get audio over the HDTV. I'm using the HDMI connection. I'm not sure how to find what video card I've got; the laptop is a HP G60 with Vista Home Premium. Help!