i3 and ULV CPUs: Battery Life

I was wondering if anyone here can answer a question that's been on my mind for quite a while. I've been researching for my next laptop purchase and I've noticed that there are quite a few i3 laptops that have pretty good battery life like the new Toshiba Portege, the 13, 14, and 15 inch Acer Timelinex models, and the Asus u30jc. Why do these laptops have such good battery life if they use standard voltage processors which are just as power hungry as last year's Core 2 Duos? And at the same time, why are the new Arrandale ULVs on the Alienware m11x and 11 inch Acer Timelinex reported to have shorter battery life than the previous models? It just doesn't make much sense to me.

Anyway, I'm just curious about the whole thing (it's not really going to affect my next purchase) and I hope someone can answer my question.

 

The answer is simple: design goals.

The U30Jc (which I have) was engineered 'perfectly' for long(er) battery life.

You can get the exact same configuration from another manufacturer and the battery life may be dismal.

This is the progress offered with each newer platform. As manufacturers get more experience with the new found capabilities the new hardware offers, the older and almost similar (ULV) last year models will be out dated.

Unless you really, really need/want 12hr run times and performance is not an issue (ever), then the ULV options are only worth it if you can save a lot of $$$ by buying them instead of the better/newer i3's.

 

Those laptop have larger batteries as well as hybrid graphic cards.

 

Intel's C2D line is the definition of efficiency, and that's hard (even for Intel) to beat. Arrandale already contains the major north bridge components, which are the memory controller, PCI Express for external graphics, integrated graphics and the DMI connector which you have to take into account when looking at TDP ratings. Once Intel brings all of their components to the same lith size, then you'll see some pretty nice improvements. Like Intel moving the graphics core to the CPU die meant that they had to shrink the graphics core to 45nm, and that in itself made GMA graphics that much more power efficient. Of course Arrandale didn't bring the battery life estimates that most of us were looking for, but the i3 ULV is much better of a processor than the SU7300 while not really taking away from the battery life of the previous generation.