Life time of battery with Mountain Lion.

Everyone have the same problem!!!

There was a report I saw that suggests 10.8.2 is a lot better, I will soon find out.

Updated with 10.8.2 soon after it released, the battery performance looked the same. Fast drain!! It lost about 10 percent after normal using for 15 minutes. After a full charge, the calculator said it had 7 hrs remaining, but actual use was much less than it said. I shut down all the running program except Safari for web browsing only. I think Apple didn't focus on battery life but busing to fix something else more important. From now on I have to carry all those AC adaptor everywhere exactly the same like Windows based PC.

I just updated. I now have 11:05 hours. Pretty good I'd say. late 2011 15" i7

Here's how I update my mac:

I make a bootable usb flash stick that has 10.8.2 on it.

There's lots of instructions out there to guide you through it.

It all starts with bypassing the updates in the App store.

From there download 10.8.2 no update here, full install.

Search online for detailed instructions, it's super simple.

Start by mounting a disk image "InstallESD.dmg) located within the mountain lion install app.

Then, using disk utility, restore your usb stick to the mountain lion "InstallESD" disk you've just mounted.

Then wait.

Once done, eject usb stick, shutdown mac.

With usb stick in your mac, boot while holding down the option key.

Choose your usb stick (That has 10.8.2 on it) and install.

All your information and data will be untouched.

I think doing it this way is better that updating, check out my batter life.

The ultimate, as many know, is to timemachine backup, wipe your drive using disk utility, boot from usb and install on a complete clean drive. Mmmmmm.... I think that's how apples grow best.

It's too bad that mac need such care when installing os but from what I've read, the above method works. Again, my mac went from 8.5 hrs. with 10.8, then 9.5 hrs. with 10.8.1, now 11:05 hours. Not bad Apple. It's too bad that mac need such care when updating but I think the extra effort is worth it. If anything goes wrong with your mac and your wifi isn't working, you now have a bootable os from your usb.

Great!!! But I've already updated. What can I do?

taweeskk,

Backup with time machine. If you can, it would be best to erase your drive using disk utility. Obviously though after making the bootable usb stick. You would then restore from your time machine. It's worth the time, you'll notice speed, battery life, etc. As I've read countless times, this is the best way a mac can be updated. Googel "is doing a clean install worth it mountain lion". Google other stuff, you'll be convinced.

If you don't want to wipe your drive, no problem. Here's what you do:

Go to the App store, search Mountain Lion in the search bar. Download. You've paid for it so it should start with no problems.

Once downloaded go into the Mountain Lion installer app in your applications folder.

Locate the "InsallESD":

Right click (tap with two fingers) on the installer icon>select "show package contents"

Browse the folder "Shared Support".

Inside "Contents" folder, locate "InstalleESD.dmg"

Launch to mount it to your desktop.

Use Disk Utility to create your usb with mountain lion. You'll put the disk image you just mounted on it.

If you want instructions on this, ask or google "disk utility restore disk". Or something like that. Find a video on it.

Once you've got your bootable usb, restart your mac (with the usb stick inserted) holding down the option key. It's booting from your usb now.

Choose the usb drive.

Choose reinstall Mountain Lion, or go to disk utility to erase your drive. Once erased, you'll go through the previous few steps.

Next you're installing.

Good luck. Reply if you need more info.