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da3dl3us
Jul 21, 2011, 03:44 PM
So I charged my battery to 100% as per the battery calibration tools. It says amount of time left on my battery is 3hours and 30 mins. I haven't done anything to the system in terms of brightness, etc.

Is this just because it hasn't been calibrated yet or is the battery life of the i7 really that poor?



OSMac
Jul 21, 2011, 03:51 PM
Check the CPU usage its probably running something at 75% or more...

da3dl3us
Jul 21, 2011, 03:53 PM
Check the CPU usage its probably running something at 75% or more...

Nope. Around 10%.

fitshaced
Jul 21, 2011, 03:56 PM
My MBA 13 i5 says 8h 40. Not expecting to get that

da3dl3us
Jul 21, 2011, 03:58 PM
My MBA 13 i5 says 8h 40. Not expecting to get that

Damn, this is not good. I hope the battery life isn't crappy on this cpu. I'm gonna give it a shot with a proper calibration and see what happens.

KPOM
Jul 21, 2011, 04:04 PM
The indicator can be notoriously unpredictable, especially at first. Once it has a chance to calibrate itself it should get better over time. By all means force a calibration if you want, but it's better to gauge battery life with a clock than by the display.

Mikael
Jul 21, 2011, 04:26 PM
Damn, this is not good. I hope the battery life isn't crappy on this cpu.
Of course it's not. The CPUs are physically the same. The only difference is that Intel has kept all cache enabled on the i7 and bumped the clock frequency by 100MHz. The effect on full load will be very small to negligible and the effect in idle should basically be nil.

da3dl3us
Jul 21, 2011, 04:38 PM
Of course it's not. The CPUs are physically the same. The only difference is that Intel has kept all cache enabled on the i7 and bumped the clock frequency by 100MHz. The effect on full load will be very small to negligible and the effect in idle should basically be nil.

Ah, you're probably right, just got a bit nervous. I'm just going to let it calibrate itself and see how it is.

Scuba629
Jul 21, 2011, 04:40 PM
Ah, you're probably right, just got a bit nervous. I'm just going to let it calibrate itself and see how it is.


Just make sure the CPU isnt working hard. I'm interested to know the reported numbers also.. You sure got yours fast. I wish my was here.

da3dl3us
Jul 21, 2011, 04:55 PM
Just make sure the CPU isnt working hard. I'm interested to know the reported numbers also.. You sure got yours fast. I wish my was here.

Picked it up in store. They had the ultimate 13'' in stock.

GGJstudios
Jul 21, 2011, 05:03 PM
So I charged my battery to 100% as per the battery calibration tools. It says amount of time left on my battery is 3hours and 30 mins.
The time indicated is an ever-changing estimate, based on the current power demands of your system, which is affected by a great number of factors, including screen brightness, WiFi, Bluetooth, apps/processes/widgets running, etc. This should answer most, if not all, of your battery questions:
Apple Notebook Battery FAQ (http://forums.macrumors.com/showpost.php?p=9875442&postcount=23)

Scuba629
Jul 21, 2011, 05:06 PM
Picked it up in store. They had the ultimate 13'' in stock.

They had the 1.8 i7 in store. Man I ordered mine online.

Apple Expert
Jul 21, 2011, 05:16 PM
They had the 1.8 i7 in store. Man I ordered mine online.

I purchased mine in store.

Scuba629
Jul 21, 2011, 05:27 PM
I purchased mine in store.

Guess the only difference is 150 dollars if you want the gift card and the education discount. hmm wonder if I should cancel my order and go up to the store.

calvol
Jul 21, 2011, 06:04 PM
If you can, put the machine in idle, close all apps/windows, and wait about 15 seconds for the battery life indicator to update. This should give you the upper end of the range.

The battery indicator will sometimes show battery life to be much lower than actually remaining, based on the instantaneous consumption of TurboBoost at that moment.

jackyyeow
Jul 21, 2011, 10:19 PM
The best way to test battery life is to record your current time and battery %. Use your laptop as how you normally use, for 30mins, then check your % again. You can get way more realistic battery life indication that way, though still not definite but enough to give you confident result.

fyrefly
Jul 22, 2011, 12:08 AM
Of course it's not. The CPUs are physically the same. The only difference is that Intel has kept all cache enabled on the i7 and bumped the clock frequency by 100MHz. The effect on full load will be very small to negligible and the effect in idle should basically be nil.

I dunno - there were numerous reports of the battery life being worse in the 2.13Ghz C2D model than the 1.86Ghz C2D model. Despite those chips being physically the same. I even noticed that I'd get barely 5Hrs of use on the 2.13 and when I switched it for the 1.86 I'd get a good 7-8.

I'm not saying the same will be the case here with the i5/i7 models, but it's certainly not unprecedented.

h00ligan
Jul 22, 2011, 01:00 AM
Mine read that way too. 15 mins later it was at 6 hrs. We will see where it settles.