If you're building an HTPC I recommend getting a board using the Geforce 8200 chipset with hybrid power.
It'll disable your video card and use the onboard when you don't need the extra processing power. It'll make the system much quieter, cooler and energy efficient.
The 780G chipset looks fantastic and probably out performs the 8200 in gaming, but the 8200 hybrid power feature is impossible to beat if you're putting together an HTPC with a separate graphics card.
If I build an HTPC any time soon I'm probably going to use one of these.