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ks-man

macrumors 6502a
Original poster
Sep 25, 2007
742
15
I used my 13.3/1.86/4GB MBA to watch football today and was pretty surprised with the poor battery results. Would this seem normal?

Took off charger at 11:45AM CST, battery 100%
Apps open - Mail, Chrome, Parallels with Win XP running, no XP apps open
11:45-12:00pm - Simple browsing, no flash running (I use FlashBlock)
12:00pm - I start up one window for NFL Sunday Ticket Online, Flash fullscreen video and one window for my Yahoo Fantasy Sports which also uses Flash. For the bulk of the time the NFL game is on fullscreen video with my Fantasy app running in the background
1:15pm - I notice my battery is down to 48% with approx 1 hr 10 min remaining. I check my screen brightness and it is at 100% (not sure why), I reduce brightness to 50%
1:15 - I use the computer same as at 12:00pm but now at 50% brightness
2:20 - My computer goes into hibernation (there was a low battery warning about 5-10 mins earlier.

So I essentially got 2 1/2 hours of usage with the bulk being heavy usage with flash. For the bulk of the time the computer was using 50-60% of the processor and the exhaust was about 3400rpm (the fan was audible but not loud). Does this usage time seem normal for what I did? I would have expected at least to get 4-5 hours with a 13.3 using flash. Also I was surprised that the battery life didn't improve at all after dropping screen brightness from 100% to 50%.

Thoughts?
 

dmelgar

macrumors 68000
Apr 29, 2005
1,588
168
Seems about right for what I've seen of the MBA power management.

It is very highly dependent on how heavily the CPU is being used. Don't use it at all, and keep the display at a low setting, and you'll far exceed its rated time, probably getting close to 11-12 hours battery life vs. 7. But run the CPU full out, and you may get 2 hours or less.

Try to find something that doesn't use flash. Make sure to try and use the latest flash that uses the GPU. You can monitor CPU utilization in Activity Monitor and sort by CPU. The other apps shouldnt be using CPU, but they can. Check the browser and the VM.
 

centymeat

macrumors member
Nov 11, 2010
32
0
I have the 1.86/4gb/128ssd as well.
My battery life seems to be around 5 hours for skype + a few apps not very CPU intensive and multiple browsers(usually with some flash) at about 70% brightness.

I haven't tried the extensions to block flash.

I get a bit more than 3 hours with some light videos (streaming low quality flash).
 

efirmage

macrumors member
Apr 13, 2010
94
0
Yeah sounds about right to me. Flash absolutely sucks the life out of this thing.
Adobe is apparently working on a MBA version of Flash, but who knows when or if that will be out.

Interesting note, after watching a streaming flash video for about 10 minutes, my CPU temp was 163F. After playing Starcraft 2 for about an hour it was 152F, and cooled down almost immediately.
 

foiden

macrumors 6502a
Dec 13, 2008
809
13
Flash Video = more demanding than Starcraft 2. :)

Actually. I was just joking, but in a way it actually has some truth behind it. The fans were the loudest, on the thing, when I was playing a 1080p youtube flash video on the 2.13Ghz Macbook 13".
 

ks-man

macrumors 6502a
Original poster
Sep 25, 2007
742
15
Unfortunately most videos for watching live sports and handling things like Fantasy are all Flash. I like watching Direct TV online and NHL Game Center for live sporting events. Also Yahoo sports which I do all my Fantasy stuff with utilizes Flash. I'm using Flash 10.1.103.19. That stinks that I can't watch a full Football or Hockey game on the Air. Not that I have a choice, but would HTML 5 really save that much in battery life? How much processor usage does a full screen HD video in HTML 5 use?
 

foiden

macrumors 6502a
Dec 13, 2008
809
13
I haven't tested here, myself. But a lot of people are already quoted to say that HTML5 is way easier on their machine. Runs cooler, longer battery life.

Now, with the news of Adobe working on a MBA-supported version of flash, this may change. Likely, we're dealing with a version of flash where the hardware acceleration stuff is broken, for the time being.
 
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