newbie question: do macbooks loose performance while operating on battery?

[rosas]

hi, I just ordered my first mac a few days ago online, and seeing that almost everyone takes advantage of the suposed 10h battery of the 13', I wonder if it gets slower when you are using the battery.

my current notebook (compal FL90) is considerably (much) slower when it is not powered to the grid especially if I'm running photoshop for casual editing.

thanks in advance

PS: english is not my native language, in case you didn't understand what i was asking, please say so.

 

[spinnerlys]

It does not get slower while using the battery. But the more CPU is used the faster the battery is drained.

 

[Intell]

I'm not sure but I think the CPU does become throttled when on just battery because the laptop knows that it only has one source of power and can't take to much.

 

[spinnerlys]

I'm not sure but I think the CPU does become throttled when on just battery because the laptop knows that it only has one source of power and can't take to much.

I used my uMBP 17" with battery and loaded the CPU with lots of calculations it had to perform, and it wasn't slower, but I haven't monitored the actual frequency, so maybe it is throttled, but my experience tells my otherwise.

 

[tekmoe]

I would think it probably runs at the same speed as when it is connected to power. The latest Intel architecture is so energy conserving these days that I don't see why it would not.

 

[w00t951]

By checking the clock frequencies, I have found that the CPU DOES THROTTLE BACK but it will increase to maximum if needed. It will just avoid doing so. The main part is with the graphics. In my 2008 MBP, the NVIDIA 9400M GT decided that it would be better suited for battery work and switched while my computer was off. In my i7, the Intel HD graphics switched on. Visual performance is slightly deteriorated, with the transitions and sheets not looking as smooth as they normally do. In Windows, however, performance is not impacted in any way, as I have successfully run MW2 at the same 45/60 FPS on my Core 2 Duo and i7 Macbook Pros.

 

[gothamm]

it runs the same on battery.


it is when you take the battery OUT and have it connected to AC power (a non-issue in the unibody laptops, since battery is integrated), that the CPU downpowers.