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Mackan

macrumors 65816
Original poster
Sep 16, 2007
1,443
113
People who are running XP or Vista on their MB/MBP, what battery life do you get compared to OS X? I've seen posts complaining about the battery life in Windows, but I don't see actual numbers. Is it one hour less for the same task in OS X compared to Windows, or what? (watching a movie, wireless surfing, screen brightness the same, etc)

I am particulary interested in knowing the battery life for the new MB with the 9400M (if MBP, please compare when using 9600M in OS X, since Windows is only able to use the 9600M).
 

Mackan

macrumors 65816
Original poster
Sep 16, 2007
1,443
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I take it not many people care about battery life in Windows. When I install it I will try to report back with a more in depth analysis. It might be interesting for a few.
 

ninjapenguinart

macrumors regular
Apr 28, 2008
184
0
I usually get around 2 maybe 3 if I am lucky under Vista.
Semi-oddly I get around 3 or maybe even 4 when I run VMFusion, but that's probably because when I run VMFusion I am not running my 9600GT, nor am I really using OS X too extensively, which means only one core is really active. Who knows.
 

Mackan

macrumors 65816
Original poster
Sep 16, 2007
1,443
113
I finally got time to install Windows XP last night on my MacBook via Boot Camp. All drivers used were Apple's Boot Camp drivers. Here's an initial report regarding the battery life and power consumption.

I downloaded and installed MobileMeter to monitor power consumption and CPU frequency. Was having trouble to get a correct frequency reading, but after changing a setting, it was 1.6 GHz. This was on default laptop power manangement mode in XP. It seems this CPU cannot go lower than 1.6 GHz (multiplier 6x), which is disappointing. As a sidenote, I have been unable to get any frequency reading in OS X. If anyone knows a program that monitors actual frequency, and not load, please inform.

The actual power consumption of the notebook were hovering around 15-16 Watts, when basically doing nothing, and having the screen at the lowest brightness setting. That's is very high. I disabled BlueTooth, Ethernet and iSight, and it came down to 13.0-14.0 Watts.

I turned the Nvidia Powermizer on and off to see if it actually mattered, and indeed, when disabled the wattage increased to 15.6 Watts.

But other than that, I don't see what other obvious out of the box things one can do to lower the power consumption. I totally lack the tools and knowledge to find out what hardware is clearly drawing more power than it should (and compare to what it draws in OS X). My battery life was showing around 2.30-2.45 hours when doing nothing and quickly decreased.

I can tell that from my experience the MacBook power consumption in Windows XP is about twice what it should be. This also confirms fine with that I get easily 5.30-6.0 hours in OS X, when basically doing nothing.

It is very possible to get the power consumption down to around 7-8 Watts on a machine like this. Several ThinkPad models with similiar specs reach these kind Wattage numbers.

I can only conclude that the MacBook hardware, it's EFI, Bios emulation, and Apple drivers, do not play well with Windows. Again, this is really not a problem with Windows. And I doubt Apple ever will put effort into power management under Windows.
 

Mackan

macrumors 65816
Original poster
Sep 16, 2007
1,443
113
After checking around a little it seems my results are rather consistent with results from people running Linux on the MacBook. Overall, the power consumption is many watts higher than in OS X even when turning off several devices such as wireless, hdd, bluetooth, etc. A lot of hardware on the MacBook must stay in a non-optimized power state. Perhaps it is the BIOS emulation done over the EFI that causes the real problem. Windows relies a bit on the BIOS to power down devices I think. Probably Linux as well. Something is fishy there.
 
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