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MacBooks take performance nosedive on AC power alone


Here's a curious thing. Gearlog is reporting that in testing a MacBook Pro, they found substantially lower performance while running on AC power alone, with the battery removed. Apparently, Apple doesn't hide this quirk; there's a Support Document claiming that this is done to prevent "the computer from shutting down if it demands more power than the A/C adapter alone can provide."

On their new unibody MacBook Pro, Gearlog noted a 36% lower processor benchmark without the battery. The upshot is simple: leave the battery in, even if you use your MacBook (Pro) at your desk. Interestingly, at the same time Apple does recommend allowing the battery to discharge at least once per month.

[via Engadget]

Here's a curious thing. Gearlog is reporting that in testing a MacBook Pro, they found substantially lower performance while running on AC...
 

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Rigved

interesting article !

similar -

MacBook Air Vs ThinkPad X300 at :

http://www.techreviews4u.com/?p=476

November 27 2008 at 5:40 AM Report abuse rate up rate down Reply
rptb1

To everyone complaining about "headline space" and repeating, over and over, that Mac portables have always done this: stop it. Can't you see that nearly all the comments so far are repeating what you just said? Can't you see there is just a little bit of a problem with complaining about repetition over and over again? Try leaving the comments for people who actually have something to say. Thanks!

November 25 2008 at 5:56 AM Report abuse rate up rate down Reply
krye

Where have you guys been? MacBooks have always done this. The original releases used to drop to 1000MHz when you pulled the battery out.

November 24 2008 at 9:24 AM Report abuse rate up rate down Reply
michaelB

Hmmmm, I suppose now I have yet another reason to replace my shot battery on my first gen Macbook pro. Thank goodness christmas is coming! Nothing like some new apple product under the tree!

November 23 2008 at 11:30 PM Report abuse rate up rate down Reply
rt

some people might want to take a look here

http://www.batteryuniversity.com/parttwo-34.htm

before stating their opinions as 'fact'

November 23 2008 at 8:25 PM Report abuse rate up rate down Reply
Simon

What's with all the stupidity here? Let's set some facts straight.

• This has always been the case. Even the iB G3 and PB G4 throttled down the processor to half the clock if you removed the battery.

• It's put in place to prevent your Mac from shutting down unexpectedly when the system (under high peak load) suddenly draws more power than the adapter can deliver (45W for the MBA, 65W for the MB, 85W for the MBP).

• There's no reason to remove your battery. Even if it's totally toast as a *battery* you don't have to remove it. Just leave it in there and use AC power. No harm done.

• Also Li ion or Li polymere batteries don't need to be removed to extend their lifetime. The only maintenance required is running them down every month or so. Removing and storing batteries to preserve battery health is completely outdated advice (dates far back to NiMh batteries).

What Apple is doing is smart and as usual they gave this a lot more thought than 99% of the Mac rumor site readers.

Now read this entire post again. Memorize it. Heed the advice. And don't forget to say thanks to me for offering you dimwits a clue. It was direly needed. ;)

November 23 2008 at 3:33 PM Report abuse rate up rate down Reply
MAXX POWER

Do people actually take their batteries out to run on AC? What if you accidentally unplug the power cord? or your power goes out? It's a built in UPS. Really sounds like nit picking to me -- especially when it's been happening for the last 3 years and no one cared.

November 23 2008 at 3:07 PM Report abuse rate up rate down Reply
Cecil Remmler

i have been to the apple store twice in the last week for some little repairs, and both times I asked how i could prolong the life of my battery. i told them that I have the MBP plugged in 90% of the time, and the apple geniuses said that the best thing to do in that case, is to remove the battery.
When I said that I had read that removing the battery will lower the performance, I got told that that "is a myth".
So I'm glad that this is being discussed here. And i'll just re-calibrate my battery once a month.
Still a bit surprised that the geniuses at the apple store don't know about this...

November 23 2008 at 3:01 PM Report abuse rate up rate down Reply
Josh Burks

it always surprises me to read these comments that have so much angst, like they are SO mad when old news comes up. Really? as quickly as the laptop culture, not just mac, is growing, you are BOUND to read a number of headlines and be like, "well duh, gosh!" but then again, 13 year old sammy and his new shiny mac or so-so dell has never heard of this. theres no need to be so arrogant and say stuff like i just CAN'T bear to hear another of these articles. I love mac, i tolerate windows, but i must say the devout Apple users are so proud and "oh-i-already-knew-that" like. simmer down, o educated ones lol.

btw, fun fact to chew on, true the battery is not continued to be charged when it is plugged in if already charged. but anyone with istat or the likes can tell you when you are doing some cpu intensive tasks you WILL notice the battery go from 100 to 99 or 98 at times. likewise a charging battery charges slower when you use the laptop heavily. this is simply just because AC power has too much amperage to be kept cool, so it is limited, thus using the battery when the wattage is needed. AND the reason the life is diminished is BECAUSE of that heat generated from the surplus of AC ampers. a battery only has a set number of recharges before it dies. and heat as we all surely know will discharge any battery lithium or alkaline. the heat discharges a bit of the battery; then it it recharged; thus a cycle is used and lost, bringing it closer to its inevitable death.

everyone seems to be on the right track, but also very narrow-eyed. put the pieces together. and for god's sake, not so angry!

Think Different. not Think Conceited.

peace

November 23 2008 at 2:07 PM Report abuse rate up rate down Reply
1 reply to Josh Burks's comment
ShiggyMozart

Amen.

November 23 2008 at 2:19 PM Report abuse rate up rate down Reply
alansky

"Interestingly, at the same time Apple does recommend allowing the battery to discharge at least once per month."

What is the point of this comment? Yes, Apple recommends discharging the battery... by unplugging and running on battery power until the battery is fully discharged. Battery removal is not recommended for this or any other operation (except disassembly of the computer).

November 23 2008 at 1:47 PM Report abuse rate up rate down Reply
1 reply to alansky's comment
ShiggyMozart

Yeah. I agree. This is a non-issue. Like many others here I've always ran my laptops (my iBook from 2001 and now my White MacBook from late 2007) with the batteries in at all times. I've only taken it out to install / replace RAM. Other than that it's been in for most of the time I've had the machine(s).

November 23 2008 at 2:16 PM Report abuse rate up rate down Reply
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