Mrjellop :
what is tpd and what is good % on it on the 7970
im pretty sure you're referring to TDP, which is thermal design power. depending on if you have a reference design HD 7970 or a non-reference HD 7970 (one example being a factory overclocked video card from gigabyte or other brands), itll use a little more power than the reference design TDP of 250w (so, @ 100% TDP, your card will be drawing 250w of power on a reference design card or most likely higher on a non-reference design card).
i dont think there's a good "%" but, if you're under 100% TDP while gaming, it's probably just the fact that the game doesn't need to use all that power.