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Yes, it does affect it's performance if you can't actually use the machine at full blast. And it's just absurd-I think a defect-to sell a system with a power supply that's too small. You'd swear people are falling over from the "weight" of these things or something :D

No, it doesn't affect performance when you run with the battery installed. There is no limitation on running full speed. I've done it many, many times and the battery remains at full charge.

The power supply has sufficient wattage to run the machine at full speed.

per Apple spec for the MacBook Pro:
DC input: 18.5 Vdc, 4.6A maximum.

18.5 * 4.6 = 85.1W

Based on Apple's reason for the clock speed reduction, I would assume the maximum current rating is continuous. The MBP might exceed this due to surges from, for example, harddrive spinup. With the battery installed, it can provide that momentary current surge.
 
Also keep in mind that when you remove the battery, you are exposing the innards of the laptop to external dust. Once the fans kick on, this newly created gaping hole may start sucking in dust and depositing it on things that should not be exposed to such dust.

I use the laptop plugged in until the battery is fully charged, then unplug it and run on battery until it full drains and the laptop goes to sleep. Let is rest for a while and plug it back in.
 
it down throttles the CPU.

both cores are still utilized. I wouldnt recommend running without the battery though. There's really no point in taking it out unless you want dust in your bay.

and at my dorm last year we had a blackout while i was using my MBP. It does happen so just leave the battery in.
 
Also keep in mind that when you remove the battery, you are exposing the innards of the laptop to external dust. Once the fans kick on, this newly created gaping hole may start sucking in dust and depositing it on things that should not be exposed to such dust.

I use the laptop plugged in until the battery is fully charged, then unplug it and run on battery until it full drains and the laptop goes to sleep. Let is rest for a while and plug it back in.

That's bad on the battery. You're better off keeping it fully charged. Lithium batteries don't like being discharged.
 
Yes, it does affect it's performance if you can't actually use the machine at full blast. And it's just absurd-I think a defect-to sell a system with a power supply that's too small. You'd swear people are falling over from the "weight" of these things or something :D

You can run the system at full blast, just that you'll run out of battery eventually. Either ways, laptops are not designed to run at full blast always and that certainly took part in the design.
 
You can run the system at full blast, just that you'll run out of battery eventually. Either ways, laptops are not designed to run at full blast always and that certainly took part in the design.

Mine will be though. So I kind of need to know ahead of time if the system can't handle that. I won't buy a system that can't run a copy of Folding for every CPU all the time.
 
Hey all,

Just curious... I run my 2.33 GHz MBP as a desktop computer with AC power a lot and usually use a secondary monitor as the main display. Since it's not the best practice to always have the MBP running off of AC power (instead of the battery) because this can decrease battery life, I was wondering if you think it'd be safe to just remove the battery from the MBP as long as I'm using it for more of a "desktop" unit than a mobile unit. I'm also using a Griffin Elevator stand (if that matter for any reason). Any thoughts?

The decrease of battery life doesn't come from running on AC power, it comes from not using the battery. You will get the same decrease if the battery is lying around somewhere, so you don't gain anything. Just use the computer unplugged every two weeks. And apart from the disadvantages that others posted, there is the risk of dirt getting into your computer or the battery getting dirty or damaged while it is outside the computer. So don't do it.
 
The decrease of battery life doesn't come from running on AC power, it comes from not using the battery. You will get the same decrease if the battery is lying around somewhere, so you don't gain anything. Just use the computer unplugged every two weeks. And apart from the disadvantages that others posted, there is the risk of dirt getting into your computer or the battery getting dirty or damaged while it is outside the computer. So don't do it.

Lithium batteries degrade naturally regardless of whether you're using them or not. They degrade faster if you do use them-they like to be kept fully charged. But officially most companies act like they have a life of two years (in reality it's more like they've lost 20% of their capacity even if you don't use them, if I'm remembering right, and even more if you do).
 
Yes, it does affect it's performance if you can't actually use the machine at full blast. And it's just absurd-I think a defect-to sell a system with a power supply that's too small. You'd swear people are falling over from the "weight" of these things or something :D

The power supply is absolutely sufficient to run at full blast permanently - when the battery is plugged in.

The battery is needed as a reserve for short moments where you use _more_ than full blast. Consider running a program that suddenly starts using both cores and the GPU at full blast, and then - just at the same time - the fans kick on, and the program starts reading from the harddisk and the DVD drive. Fans, harddisk and DVD drive accelerate all at the same time. That takes extra power, only for a second or so.

Since nobody uses the MBP without battery, it would be a pointless waste of money to make a bigger, heavier and more expensive power supply just for that rare situation. Instead, Apple supplied a cheap and reliable temporary solution.
 
You can run the system at full blast, just that you'll run out of battery eventually. Either ways, laptops are not designed to run at full blast always and that certainly took part in the design.

It's hard to run at "full blast". You would have to keep the CPU, the GPU, the harddisk, and the DVD drive running and doing things simultaneously all the time. For example, running Handbrake continuously won't manage to uncharge your battery, because the GPU doesn't do much, and the DVD drive and harddisk are not actively reading/writing most of the time. You'd probably have to write a program specifically to achieve this.
 
The power supply is absolutely sufficient to run at full blast permanently - when the battery is plugged in.

The battery is needed as a reserve for short moments where you use _more_ than full blast. Consider running a program that suddenly starts using both cores and the GPU at full blast, and then - just at the same time - the fans kick on, and the program starts reading from the harddisk and the DVD drive. Fans, harddisk and DVD drive accelerate all at the same time. That takes extra power, only for a second or so.

Since nobody uses the MBP without battery, it would be a pointless waste of money to make a bigger, heavier and more expensive power supply just for that rare situation. Instead, Apple supplied a cheap and reliable temporary solution.

Okay, that's not TOO unreasonable I guess, though I'd prefer it be a bit larger to compensate.

As long as it can run the CPU and GPU continuously at full blast without issue...
 
just leave the battery in, it does no harm to your system or to the battery. When your battery is fully charged it does not charge anymore, and there therefore does not cause any damage.

leave the battery in when its fully charged it like its running on A/C power without the battery, but you dont get your cores slowed down, and if a power outage occurs it wont mess up your Mac because your battery is in.
 
Lithium batteries degrade naturally regardless of whether you're using them or not. They degrade faster if you do use them-they like to be kept fully charged.

Lithium ion batteries actually degrade faster if they're kept fully charged all of the time, which is the reason why Apple specifically recommends not keeping your portable plugged in all of the time.
 
I tried running my 2.16 MBP Core Duo without the battery. According to the CoreDuoTemp utility, my MBP did clock down to 1 GHz, even when running under a heavy load. In Activity Monitor, it appeared to have access to both cores.

The MBP immediately went back to 2.17 GHz when I put the battery back in.

So, my real world experiment verifies what many people have noted.
 
Lithium ion batteries actually degrade faster if they're kept fully charged all of the time, which is the reason why Apple specifically recommends not keeping your portable plugged in all of the time.

Taking care of Lithium ion battery seem closer from sorcery than science.

I mean, everyone have their own belief and ritual regarding this.
 
Taking care of Lithium ion battery seem closer from sorcery than science.

I mean, everyone have their own belief and ritual regarding this.

There is no sorcery involved, only fact and fiction. And plenty of fiction has been told on this forum.

The properties of the various battery technologies are well-known and there are a few simple guidelines to follow if you want to maximize the longevity of your battery. I would suggest reading all the info available on Lithium Ion batteries at www.batteryuniversity.com for a good primer on the subject. There's also info on other battery types as well, if you're interested.
 
The charger does not have enough power to run both cores, as someone already said. It is a "charger" after all, not an external power supply. It can act as one, but is not designed for that.

What the hell are you talking about, if it's not a power supply, what is it doing then? What exactly is the difference between a "charger" and a power supply?????? The only thing making it a "charger" is the fact that the battery is charging itself off of it. If I hooked up a computer power supply to a battery, is it now magically a charger and not a power supply? :confused::confused::confused:
 
What the hell are you talking about, if it's not a power supply, what is it doing then? What exactly is the difference between a "charger" and a power supply?????? The only thing making it a "charger" is the fact that the battery is charging itself off of it. If I hooked up a computer power supply to a battery, is it now magically a charger and not a power supply? :confused::confused::confused:

What i'm trying to say is that the MBP charger is not a full-blown power supply as you would find in desktops. It is not designed for that, it is designed to be a charger, to charge a battery, that's the difference.
 
As Overcast says, that's a silly distinction. It's a power supply. It should have enough power for a worst case scenario. Anything less is putting looks over function-which Apple does far too often I think. Either that or they're just saving a few cents by including a smaller PSU.
 
As Overcast says, that's a silly distinction. It's a power supply. It should have enough power for a worst case scenario. Anything less is putting looks over function-which Apple does far too often I think/. Either that or they're just saving a few cents by including a smaller PSU.


-Yeah, one that is designed to charge a battery

-And this is relevant to the topic?
 
A few weeks ago my battery had to be sent back to Apple and so I was running on AC for a week and a half and I noticed no decrease in my clock speed. Most people probably don't keep track of their clock speed like I do, but I have it in my menu bar, so yeah I know what it is pretty much all the time :)

I know the Apple doc contradicts my experience, but I'm just saying it as it was.

Also, I'm not sure of how truthful this is, but I heard a report that the Core 2s can't actually turn off one of the cores to conserve energy. When one core is disabled supposedly that core just runs at 100% with some dummy process. Don't quote me on that though ;)
 
A few weeks ago my battery had to be sent back to Apple and so I was running on AC for a week and a half and I noticed no decrease in my clock speed. Most people probably don't keep track of their clock speed like I do, but I have it in my menu bar, so yeah I know what it is pretty much all the time :)

I know the Apple doc contradicts my experience, but I'm just saying it as it was.

Also, I'm not sure of how truthful this is, but I heard a report that the Core 2s can't actually turn off one of the cores to conserve energy. When one core is disabled supposedly that core just runs at 100% with some dummy process. Don't quote me on that though ;)
When one core is disabled, it's not running anything at 100%.
 
I ask about that issue to my local apple technician,
he said that if you want to have your logicboard burned , just plug the magsafe without battery
 
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