Quote Originally Posted by curaga View Post
Only if the big GPU can't go low enough in idle/2d modes. This is constantly improving, so in a generation or two only the most high-end mobile GPUs should require an integrated one too to keep power in check.
Except that all the CPUs just have GPUs built in anyway, and they're almost guaranteed to be more power efficient than keeping an entire second board powered, even in very low idle states, due to having integrated power regulation circuitry and not needing to keep an interconnect/bus powered.