Intel Core i7 720QM vs Intel Atom? Which is better in power saving?

Defiantly the i7 uses more power. But the whole system will use more power as well. The i7 has a higher powered graphics chip, a 7200RPM hard drive and most likely 3 sticks of ram. Not to mention that the wattage of the i7 is much higher than that of the ATOM. The atom most likely only has a 5400RPM hard drive, and only 2 sticks of ram at best. So all that combination factors out why your i7 doesn't stand up green... But this shouldn't be too ironic to you...