In COD4, hardly the most accurate performance test - also, as I said, some games it has almost no effect on, others (I would presume the ones that use the most video memory, such as GTA4) it will have a big effect.
Ftr, my PC with an E5200 and HD4830 uses less power than a PS3
From the results I've seen, the i7 idle results are far from exemplary.