Originally Posted by Benetanegia
We have no idea what the TDP for that chip is. Running at 200 Mhz less can vastly affect the power consumption. Much lower voltages might be needed and I really mean MUCH lower voltages. Fermi consumes that much because it's leaky and 40nm process is very leaky too, Fermi is the sum of both facts. But what applies at 600Mhz++ might not apply at below 500mhz.
Performance wise it looks much faster than both 285M and Mobility 5870, even at 425Mhz, considering that we can say that their desktop counterparts are the 9800GT and 4850 respectively.
480M's TDP is 100W.
For refrence, RM 5870's TDP is 50W.
The RM 5870 is directly comparable to the Radeon HD 5750.
The 285M is more like a 9800GTX with lower clocks but it's still faster than a 9800GT.
Xbit has a review of a Geforce GTX 465:
352 shaders - 608Mhz core - 1215Mhz shader - 102.7GB/s mem
If you take the GTX 465 results and take around 30% off then you'll get the idea of how the GTX 480M will perform.
Even if it's faster, at what cost did it become faster?
Double the TDP, 3x bigger silicon, more complex PCB, ...
I mean, you can have a RM 5870 CF in the same power envelope beat the crap of the GTX480M.