Macbook Air Battery Life inconsistencies after Migration

[Sfdoddsy]

My old MBA is running out of disc space and after 800 cycles the battery only lasts a few hours.

So I appropriated my wife's when she upgraded to a 12" Macbook.

However, I'm getting really weird battery life issues.

When I tried it with her stuff still on it, it would show 5-6 hours or so on a full charge (it has 250 cycles).

But when I wiped the hard drive, reinstalled OS X and migrated my stuff, that dropped to 3 hours. About the same as my old MBA.

So I wiped it gain and reinstalled OS X and didn't migrate my stuff. Now I got 7-8 hours.

Then I migrated my stuff (apps and user ID) and it went back down to 3 hours. I thought it might be Spotlight indexing, but after waiting for that to finish there was no improvement.

So I wiped it again, reinstalled OS X, did not migrate anything, and just for the heck of it blocked Spotlight from seeing the hard drive.

Now the counter is showing 12.30 hours of battery life.

3 hours to 12 hours is a massive difference.

Any thoughts what might cause this?

 

[keysofanxiety]

Well it has to be something you're migrating over. Startup items, login items, application caches, fonts, background processes, widgets, 3rd party resource monitors -- it could be anything, really. There are so many things that can cause the battery issues you're mentioning.

 

[JohnDS]

Try resetting the SMC: https://support.apple.com/en-ca/HT201295

 

[satcomer]

I said it million times, after an "update" run the free application EtreCheck. Plus with your Migration (especially if you transferred EVERYTHING) because the text output will tell you if you transferred old hacks or startup baddies! This way you can manually delete old, bad files and speed up your Mac.

 

[shtyage3]

The 2010 revision includes two speakers for stereo sound while earlier versions have one speaker located under the keyboard. The 2011 update has a 1280×720 FaceTime HD Camera, replacing the previous 640×480 iSight camera. The 2012 update replaces USB 2 with the twice-as-fast USB 3, and uses the MagSafe 2 connector instead of the original MagSafe connector, for charging purpose.

 

[Sfdoddsy]

Thanks for the suggestions.

After trying various combinations of resets after using Migration, I decided to just bite the bullet and start from scratch. I did a clean install and got decent battery life. Then I added files and programs manually to the new user ID.

It is somewhat dismaying that the battery life before adding any programs (11 hours indicated after full charge and nothing open) is so much better than it is once my files, Office and a few other bits and pieces have been installed (8 hours indicated) but it is still way better than when I transferred all files, programs and user settings using Migration.

One of the reasons I switched computers was poor battery life, so I can't help wondering what my old Air would achieve with a clean install. It doesn't seem like a coincidence that the battery life after migration of the newer Air was almost identical to the older when both were running clones of each other.