I'm waiting for delivery on that one also. My guess will be about 2-3 hours max with 12 cell batteries. My Compaq pentium M Centrino runs about 6.5 hours with 12 cell batteries.
It depends on the processor you pick also. I keep reading different things about the new 4000+ AMD. Some says that it draws 15 watts more than 3000+ AMD.
Does anyone know the approximate battery life of the Compaq R4000 line? They seem to be a pretty good deal, and I was wondering if it's worth it.

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