First off, I'm not really sure if this can fully answer your question or not, but I'll say it anyways. Mobile graphics cards are usually one tier or level below their desktop one with the same name. For example, a mobile 6770 performs at the level of a desktop 6670. This isn't exact, but it's a pretty good measure for their power.
Secondly, the Intel HD graphics integrated into the processor provides absolutely no additional power if you are using a dedicated card. The new line of AMD processors allow this, but not intel. If there is not dedicated card, the integrated one is your only graphics card. There is also a technology by Nvidia called "Optimus" that is used on laptops that have both integrated graphics and dedicated gpu's. This allows demanding programs, such as games, use the dedicated gpu, while browsing the web/on desktop the integrated card will be used to save power.
First off, I'm not really sure if this can fully answer your question or not, but I'll say it anyways. Mobile graphics cards are usually one tier or level below their desktop one with the same name. For example, a mobile 6770 performs at the level of a desktop 6670. This isn't exact, but it's a pretty good measure for their power.
Secondly, the Intel HD graphics integrated into the processor provides absolutely no additional power if you are using a dedicated card. The new line of AMD processors allow this, but not intel. If there is not dedicated card, the integrated one is your only graphics card. There is also a technology by Nvidia called "Optimus" that is used on laptops that have both integrated graphics and dedicated gpu's. This allows demanding programs, such as games, use the dedicated gpu, while browsing the web/on desktop the integrated card will be used to save power.