Comparing Sandy Bridge Processors in the XPS 15

Starting in my thread http://forum.notebookreview.com/dell-xps-studio-xps/564110-xps-sandy-bridge-battery-life-2.html I wondered whether there was a big difference in battery life between the sandy bridge processors. To at least a first apprxoximation, it appears that at near-idle conditions, it is largely the same.

But I'd like to actually find out by having people do the same things I did with their laptops which are nearly identical except for the processor. See my last post of that thread for details on how to repeat my tests.

It may not be the best way to compare processors, but it should be a good start.

The big questions we have are: is the faster dual-core (2620M) better at single- and dual-core optimized tasks than the slower (2630QM) or roughly comparable (2720QM) quad-core? Or is the dual-core more power efficient for those tasks?

These power-draw numbers are after subtracting the "idle" power draw, though it would also be interesting to see if the idle power draw (1.37 W for me in the conditions described) would be higher or lower with a different processor.

One thing that was really surprising to me is that in the single-threaded task, both cores were in TurboBoost, rather than one being shut down or downclocked--the slightly boosted speed in the 1 core was on top of the 2-core TurboBoost level.