MacBook and MacBookPro suffer performance anxiety once the battery is removed
By Joseph L. Flatley 
posted November 22nd 2008 4:23AM
posted November 22nd 2008 4:23AM
Are you one of those thrifty-types who's always looking for an angle, always trying to stretch every last penny? You know who we're talking about: Montel Williams bases whole episodes around you, the kind of person who reuses tea bags and separates sheets of triple-ply paper towels. Unfortunately, it now looks like you now have one less trick at your disposal. According to Zach Honig over at Gearlog, running your MacBook or MacBookPro without its battery (trying to squeeze out an extra month or two of battery life) will cause a significant performance decrease: we're talking upwards of 40 percent. When he checked Apple's knowledgebase, it turns out that this is by design -- processor speed is reduced when the machine detects that its relying solely on A/C to prevent it from demanding more power than the adapter alone can provide (and any nasty shutdowns that would result). We don't know if we buy this line of reasoning, but one thing is certain: if you know what's good for you, you'll leave that battery where it belongs.
Crazy J...your comment makes now sense....if the laptop takes power from the battery AND the AC when plugged in and only from the battery when it's not plugged in, how does the battery ever charge?
@rykaro
that is true. When the Laptop is running at absolut full power (which is not as a stationary state), the battery will not be charged...
@rykaro, Are you serious? The battery + ac power > required for max CPU. The rest is charging the battery. When maxing the CPU the battery will take longer to charge.
Well there is a very easy explanation for this...
-> you (or Apple in this case) want to make the smallest possible AC Adaptor
-> so you are going to size it for the maximum AVERAGE power to be expected
The Battery is your buffer - of course providing a lot higher power for a limited time
Without the Battery your max Power is the expected max AVERAGE power.
This is actually pretty clever. And it helps all those "normal" people who leave their battery in, because they only have a small wallwart to carry.
We do the same thing on electric powertrains: Here the Battery is a high energy type, that can only provide the max average power (for topspeed). But we need a lot more power for short terms of course. That is what a small high power type pack or supercaps are for.
Just like every sane mind does it on a range extended EV. Just that in this case the RE can only provide average power and the battery max power.
All those complaining here would probably also take their battery out of their RE-EV and still expect max power ;-)
regards, wisi
So what you're saying is that if you encode a movie, and copy files at the same time, and render a 3d scene all at the same time, your laptop will slowly die and not be able to charge, and eventually shutdown.
And then you proceed to conclude that this is normal.
@petrol
Well yes, in a theoretical way that is true. Whereas I am not enough of an IT Person to tell you if there is a realworld usecase, that will actually lead to this behaviour. And of course there is a safety window so this will not happen.
To put it with the RE-EV: If you try to race up the pikes peak with your Chevy Volt: It will not be able to charge the battery... But GM is not going to put in a 300KW RE because someone might someday want to do this ;-)
@Pretol.
No, the PM system will slow the machine down to draw less power.
There is no reason to remove the battery, Lithium Ion is so unstable it's pointless to start unplugging/removing the battery IT has helped on one of my old notebooks, made no difference to two others. Just budget to replace the battery at some point they are usually quite cheap. Well non-apple ones are anyway.
It has always been there, in all release of all apple notebooks.
It is to be sure that the laptop will be able to go in sleep mode in less than 1second
if you cut AC power without a battery plugged in.
Move on!
All arguments aside, there is always a small chance that a battery will blow up or do some damage.
I consider removing the chemical battery a safety measure and not a money saver.I do not want a hot battery running 24/7.Thats asking for trouble.
This is an awesome undocumented advance in consumer power technology.
GHEY.
I'm certainly not buying a MacBook any time soon. I'll continue to use my battery-less Mac mini :))
Ahh... more surprises from the MacBook. I know my HP Pavillion dv6707us has the same issue, also the perfomance decreases once I'm running on battery. (Vista/4GB Ram/1.9ghz Dual-Core AMD 64)
And on my new MacBook, everything has been fine so far. And Windows runs nice :). I love my laptops.
Does this "fruit" stupidity ever end?
Well, this tips my scale to "no". I want a laptop for portability, but I don't plan on porting it around very often, and 100% performance on AC power is absolutely imperative.
I forgot to add: I just wouldn't want to use a laptop day after day with the battery needlessly working towards its death.
Well, I guess the MacBook is not as perfect as the fanatics claim it is.
I'm thinking that if you're really looking to stretch every last penny, you probably wouldn't be buying a Mac.
Exactly. That demographic is a very vocal internet minority that doesn't buy anything anyhow.
Hmm, turns out I inadvertently noticed this while playing with a MacBook at Best Buy (they didn't have batteries in them, I guess so people wouldn't steal them). It was hanging and running pretty slowly on their demo video thing, and gave me a pretty bad impression.
People who would go out of their way to take a battery out to put it in the fridge so that they can save 10% of the power it'll generate over the course of a year are not part of apple's target demographic anyhow.
If you're that cheap you're an idiot if you buy a mac anyhow, as similar (as far as you're concerned) hardware could be had for at least 10% less. It's obviously in your best interest to run linux since having time to dick around with batteries implies time to work on setting up a linux system to your liking.
People with money can be cheap, too. In fact, being cheap is one way many people get rich. Just not the 'tards driving Hummers on 24's.
Just tried Xbench on my 2.4 Ghz early 2008 Macbook Pro and got 186 with battery and 109 without. Quite a huge difference!
So glad my Dell ATG D630 came with the 95 watt power supply, and an additional 65 watt, yes i use them interchangeably depending on what i'm doing, sitting on the couch i take my battery out because my laptop gets less warmer that way and its a lot liter. sucks you cannot do that with a MBP :(
It's not just Apple, and it is a feature, at least compared to a fleet of Lenovos at my school that require the battery while on AC: they instantaneously shutdown when you initiate a CPU intensive task on AC only...
Holy crap, I'll have to take back my post saying I can't imagine that any laptop could draw more peak power than the adapter provides.
My research shows that running triple-ply paper towels on just one ply, also causes a significant performance decrease.
For everyone crying about this you need to learn more about computers because apple is NOT the only company who does this. IBM, HP, Compaq, etc all the laptop brands do this, some don't even run if you don't have a battery plugged in. This is because laptop power supplies cannot usually supply sufficient power alone for faster laptops, it has to use the battery every now and then. Be glad all apple does is cut performance, some brands and models I've worked on actually just shut off with no warning if it needs more power then the power supply can provide.
Surely the other way around would make more sense: performance drops when it's on battery alone, ala alienware.
So it'll do this when the the battery is really low too?
I think power brick have enough power to supply macbook pro running Crysis ax max detail, but due to thin cables and poor mag connector, it cannot handle very short spikes required sometimes in normal operation. So I think battery is used as capacitor - because regular capacitors could be too big to fit inside laptop... just look inside desktop PC - you will see groups of for example 1500uF or larger capactiors spread on PCB.
This is mytheory... but still hate apple for doing this.
Those are rectifier capacitors which help turn AC from the wall into DC for your computer. They have absolutely nothing to do with power management.
I figured I'd chime in with some results from a kill-a-watt meter I have. I have a Dell XPS M1210 laptop that I can pull the battery out and game on, the power draw never exceeds about 45 watts. If the battery is discharged and I try to do both, the battery charges slowly, but the power draw will read exactly 65 watts, the rated output of the power supply. Needless to say, the battery will charge will charge, but slowly. However, that power supply is a brick. A power supply has to convert 120v AC to 12-24v DC. In order to do this, it passes the current through very thin, tightly wound copper coils. These coils add resistance to the electrical current, creating heat. Now, everyone knows that Mac power adapters are very small. Apple has not developed some new ultra-efficient power adapter, they have to follow the same rules of electricity that everyone else does. However, in order to make them so small, they have reduced the heat dissipation ability of the adapter. So even though they are rated for 65 watts of output, they really can't do that continuously without getting incredibly hot, as they often do. This leads us to the situation where the battery is not present. Due to the design of Apple laptops, the laptop is unable to determine the power draw of the laptop without a battery. Without this information, the laptop could draw 65 watts (or more) continuously, creating a fire hazard around the scorching hot AC adapter (the reason Apple breaks with the norm and plugs directly into the wall, for increased heat dissipation). So, in effect, it is the very design of the adapter, not necessarily cheap components, that lead to the laptop artificially reducing it's power draw without a battery present.
Err... That sounds like a load of horse crap.
For a start, the whole thing about mac PS's plugging directly into the wall for added heat dissipation is crap, if that was the case, why would they provide an extension cable to replace the plug. The only reason they give you the plug as well is because it saves a lot of room.
Whats more, to use your XPS analogy, my XPS M1710 does the exact same thing, and that has a 120W power supply, and yet if I pull out the battery it will drop the Clock speed and has completely died if I have tried to play a game without the battery in.
Well maybe the California attitude is over, it seems that now Apple is touting out products that make you the sucker by limiting something in some way. iPods and iPhones without user-friendly battery changes, older Macbooks that you cannot change too many parts on, newer Macbooks that want to use up your battery so you shell out for a new one, device firmware that doesn't allow you to downgrade in case you choose not adopt the newer version. Seems like Microsoft now, Vista whether you like it or not and then it will be Windows 7 whether you like it or not, and Xbox Live new NXE no downgrades allowed. It's no longer about consumers but what companies think you should have. Tsk tsk....
I was going to get a new Macbook since I'm primarily a stationary user, but I'll get a DELL for sure now.
yeah, just a shame your DELL will the exact same and than fall apart in 6 months time
Wow and people still buy this crap.....
So does this mean that if I am using a macbook while charging, it will STILL drain the battery because it can't get enough juice from the wall?!?!?!?!?!
Just another reason for me not to buy a MacBook
Does this remind anybody how the iPhone and iPod touches, when plugged into a USB port and in use will drain battery, but if plugged into the socket it won't and it'll charge?
Lol I love all the posts where people say "I'm going to buy a DELL now". I work on a ton of dells at my company because they are usually the first to break.
@Chris yeah but at least I won't have to send it back to Apple for repair like you would a Macbook which by the way overheat, have exploding or battery burnouts, that have issues with displays, issues with firmwares, and mouse clicking problems. Yeah Apple is a much superior product for sure, I have an older iMac Late 2006, no problems whats so ever and a DELL Inspiron 1300 never had any issues at all. Oh yes and I don't need an Apple Care either, just a waste of money, anyone that sells warranties after year of regular use obviously has no faith in their own products.
I have a Lenovo notebook with a 65Watt power supply and it does fine with out the battery in the notebook even when gaming. It still runs at full 2.4Ghz when gaming. The power supply actually gets much hotter when the notebook is doing normal task and charging the battery at the same time. So I call BS that the power supply can't supply enough power. Apple just wants you to spend more money.
People shouldn't be turning this into a fan fight, it should instead be a warning about a philosophy developed after the DRM model in which companies are now adopting by limiting the use of a product at the hardware level for purposes of revenue, region control, and THEIR approved usage or interaction with software, networks, and/or other products.
Try it with your laptop...it probably won't like it either.
Could the reason that my G4 PowerBook runs so slow be that I rely on the power supply while the OEM battery has been dead for 4 years?
Just leave the fucking battery in the fucking computer...fuckin' nerds.
I'm gonna have to call BS on Apple's reasoning for this, and also... call BS on the people who claim that LiIons will continually lose their charge if left in the laptop despite having a power brick plugged in at all times.
I had a Compaq Presario R3000 system, AMD64 3800+ (2.4Ghz) CPU in it, if you remember those models, they were rather thick and bulky. This was a desktop replacement laptop for me, something I occasionally did use on battery power only... but for 99% of the time I had it, it was left plugged in on AC with the battery inside the system AND left on for 24 hours a day. This was my primary system and I used it extensively. When idle, it ran Folding@Home. That CPU was fairly well pegged the majority of the time.
When I ordered it, I upgraded to the 9 cell extended battery. I never ended up draining it past 80% whenever I unplugged AC.
I had this laptop for 3 1/2 years.
I decided to upgrade and got a new laptop, sold the Compaq on eBay. Before I listed it, I ran it through every diag and benchmark program I had to test, verify that everything was in full working condition and measured the wear on the system.
The battery, remember, 3 1/2 years being left on 24/7 on AC except for that 1% where it ran off battery power...
Only lost 4% of its total capacity. Not 40%. 4%.
The battery model was HSTNN-DB03. 6600mAh capacity.
Notebook Hardware Control is a great program for Windows for getting battery information. I still have the screenshot for when I listed it on eBay.
Voltage: 16609 mV
Capacity: 84656 mWh
Full Capacity: 84656 mWh
Wear Level: 4%
3 1/2 years of being left on AC.
Apple has absolutely no excuse to be playing these games and anyone who thinks that batteries naturally just decay to or by 40% after a year even if you leave the laptop on full AC power are either:
1) Fools for thinking this is normal
or
2) Being fooled by the company for such a crappy design that ends up prematurely aging the battery.
If not both.
Here's the screenshot for those who want to see for themselves: http://ergh.org/misc/compaqbattery.png
Also worth nothing: Neither this Compaq, or my current laptop, dropped/will drop in CPU performance when I take out the battery while the AC brick plugged in.
My current laptop is an ASUS G1. I've had it for one year and 3 months. Its wear level is 0%. Like my Compaq, it's only had to be on battery power (power outage, tripped circuit breaker or moving it to another room) for a total of maybe 2 hours over the last 15 months.
Oh, and the brick is huge. Want a cute tiny little brick? Well, I'll go for function and well manufactured components over form and pretty looking crap.
Actually I've been using my Inspiron 1300 without the batter after I had to buy a new one because it died when I used it all the time with the system plugged in, and I haven't noticed anything at all in the part performance.