Avee's Place

Simple thoughts in a complex life

Tag Archives: snow leopard

Snow Leopard Unibody MBP Battery Life Test #4 : Real-World Usage 2

For the last test, since daily usage would vary from day to day, I did 3 runs, so that the result would better represent the case.

1st Run

What I did : Edited Google Wave documents, worked with some flash documents, listened to music and the occasional chat.
Running programs : Firefox, iTunes, Adium, TextEdit
Environment : Worked at a bright location, so screen should be at 100% most of the time
The result : Battery is down 53% in 149 minutes, average battery usage is 0.355704 % per minute, 100% battery would approximately equal to 4 hours and 41 minutes.

2nd Run

What I did : Web-based administration, server administration (using SSH), email, and a bit of coding in Windows through Remote Desktop Connection
Running programs : Firefox, Mail, Adium, TextEdit, Activity Monitor, Terminal (SSH), Remote Desktop Connection, Google Chrome
Environment : Worked at a relatively bright room, screen is probably about 70% to 100%
The result : Battery is down 60% in 134 minutes, average battery usage is 0.4477612 % per minute, 100% battery would approximately equal to 3 hours and 43 minutes.

3rd Run

What I did : Web-based administration, browsing some websites, email, encoded two 20-minutes long videos using HandBrake, internet connection using bluetooth
Running programs : Firefox, Mail, Handbrake, TextEdit, OpenOffice.org
Environment : Room wasn’t so bright, screen is probably about 70% to 80%
The result : Battery is down 65% in 119 minutes, average battery usage is 0.5462185 % per minute, 100% battery would approximately equal to 3 hours and 3 minutes.

Ok, since all of the tests have been completed, next I will try to write a conclusion from my tests.

Snow Leopard Unibody MBP Battery Life Test #5 : The Apple Test 2

It turns out that I need a lot of time just to complete the Mac Book Pro battery test. Well, I have completed item #5 in my checklist, which is to repeat the battery test as close enough to the way Apple tested them after a clean install of Snow Leopard.

As with item #2 I did a partial using Apple scenario, only this time I did not start from 100%. I take notes of the battery usage while I was browsing quite heavily searching for the best computer spec for my brother in law. The only applications running were Firefox and TextEdit. We were in a relatively dark room and I constantly adjusted the brightness to be at 50%.

The result : my battery is down 29% in 97 minutes. The average battery usage is 0.2989% per minute, which means 100% battery life would approximately equal to 334 minutes or 5 hours and 34 minutes of usage.

That is not so bad, considering that I was browsing heavily that day, the fans even turned on, something that I do not experience much.

Fixing Snow Leopard Unibody MacBook Pro Battery Life Problems

mac-batteryEver since I upgraded the OS of my Early 2009 13″ MBP to Snow Leopard, I have a problem with the notebook’s battery life. When I was using Leopard, the battery could last very long, so long that I was used to working without connecting the notebook with a power source. I also remember that the Time indicator for the battery used to estimate about 7 hours or so of battery life at 100%, although it occasionally fell to 3 or 4 hours on heavy usage. But now, at 100% it would only show about 5 hours max.

For some time I used to think that this was probably due to 64-bit architecture change that caused the notebook to use more power. But the longer I used the notebook in this condition, the more I worry about the battery. According to Apple, the new battery technology in unibody Macs are supposed to last for 1000 charge cycles, about 3 years of normal usage. The battery problem means that I am using more cycles than it is supposed to be for a given time, which increases the possibility of the battery having degraded performance before the 3-years mark.

So I googled around a bit, and found out that other people are also experiencing the same problem. The solution to this problem is to do the following :

  1. Reset the PRAM.
  2. Reset the SMC.
  3. Recalibrate the battery.

I did all three and the problem is now fixed, I can now see the 6+ hours battery life indicator on 99% again :).

~7 hrs on 99%


EDIT : I am conducting a battery test to see the actual performance of the MBP’s battery here.