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rickeames

macrumors 6502
Original poster
Mar 12, 2008
392
71
Wow -- I have been running on the "better battery" mode for a while and tonight switched to "performance." My reported battery time is half of what it was the other way.

Really?
 
I have only noticed around a 15 minute difference between running the computer with the GeForce 9600M GT vs the GeForce 9400M. I find that the 9400M is more than adequate for most uses and actually haven't taken advantage of the 9600M GT all that much.
 
Hmmm, well I'm used to getting 3.5 and right now it's telling me 1.5 hours left with about 80% charge, so it's obviously very confused.
 
Hmmm, well I'm used to getting 3.5 and right now it's telling me 1.5 hours left with about 80% charge, so it's obviously very confused.
It also tries to estimate the time by the amount of usage and the type of CPU usage at the time, etc. Make sure you have calibrated your battery as well.
 
Do you have to calibrate it for each mode? I have calibrated the battery -- in better perf mode I get 3.5 hours. I get only 2 in the higher perf mode.
 
Do you have to calibrate it for each mode? I have calibrated the battery -- in better perf mode I get 3.5 hours. I get only 2 in the higher perf mode.

No calibration is to give the battery's internal processor a chance to get a feel for its min and max charge, and to "exercise" the molecules of the battery or something like that. Honestly, I've found that time remaining thing will bounce up and down by 30 mins plus depending on what your doing and how much charge you have left
 
Do you have to calibrate it for each mode? I have calibrated the battery -- in better perf mode I get 3.5 hours. I get only 2 in the higher perf mode.

Depending on what you are going, it sounds about right. I'm getting about 2.5 hours on better performance and 3.5 hours on better battery on the 2.8GHz.
 
The same thing happens to me when I switch to the high performance chip. The battery life basically cuts in half.

Anyway, I've found that the time remaining isn't entirely accurate because it is based on whatever you are doing in that point in time. For example, I was playing a 3D game through VMWare on battery power, and the warning came up for 10 minutes of battery life left, but I closed the game & VM and lowered the screen brightness a few notches and I was able to squeeze 40 minutes out of it.
 
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