7950 do have good hash to watt ratio... but you got to lower your hash rate.
best i could do is 5 * 580khash for just over 1000watts
soon as i go over 600 khash it can EASILY go over 250watts each card.
your power consumption is about right but if you really want to save on power you have to shave off the hash rates.
if only btc diff was lower because i was doing 5 * 550 mhash for 840 watts!!!
sucks to pay 27c/kw