Advice on a new Mac

[Oxide Blu]

When the MacBook Pro is sitting on my desktop I have it plugged in to AC power but have the battery removed. This prevents the battery from going bad. The guys at the Apple Genius Bar recommend this in fact.

With the new models that have a non removable battery you can't do this. Bad for battery longevity.

I think that is one of those techno-wives tales held over from the NiCad battery days. Today mobile computers are using Li Ion batts, not the same problem with "training" like a NiCad.

Your battery will last longer if you leave it plugged in on a float charge. Your computer should be good for that. Batteries are a chemical process, always in a state of decay, no way to stop it. The best we can do is provide a stable environment to prolong the rate of decay. That is what a float charge does, a very low current at high voltage to keep the battery 'topped off' so that it isn't going up and down, e.g. "cycling".

A battery "cycle" is anytime you discharge a battery below 90% of its capacity, e.g. 10% discharge on your computer's batt meter. A battery can only be "cycled" (discharged/recharged) so many times (300 - 500 depending on depth of discharge), then it craps on your shoe. Leaving a battery in your computer keeps it from cycling, helps it to last longer. Without a float charge a Li Ion batt will self discharge at something like 5%/month. So in as little as 2-months, you lost 1 battery cycle by not leaving the batt in your computer.

The only way there is an advantage to removing your batt when your computer is on AC is if iApple does not have a modern battery charging scheme integrated into their laptops. I just don't see that.

Put your batt back into your computer when it is on AC. :thumbup:



ETA: there is a phenomonon with Li Ion batteries -- if totally 100% discharged a cell can reverse polarity. A battery is actually made up of several cells, in series, inside of the battery case. One of those cells can reverse polarity; e.g. the anode becomes the cathode, and vis a versa. Some folks have been able to recover from that situation, some cannot, battery must be trashed. Do not totally discharge a Li Ion battery.

 

[LJL]

What you are saying is the theory for these Li Ion batteries. The reality is that they do get wonky if left plugged in all the time. I just replaced one in my MBP. I was a rather diligent caretaker from the start. That was the third battery in a couple years. For the last few weeks, I had left it plugged into AC without ever going to battery use. Something went horribly wrong inside the battery chip. It was alternately saying fully charged then empty. When unplugged at fully charged state, it would die suddenly in 10 minutes or less. Guy was having same sort of problem with his. I took mine to Apple. They put it on a their fancy battery testing device that checks each cell and entire sectors individually. It said "O.K." Funny thing was that it also said 10 hours remaining charge! Not real. Battery then died instantly, while still showing full charge on meters. Go figure. Apple guru postulated that the internal battery chip went haywire. If not that, then there is something else wrong on the logic board (which was replaced about 16 months ago, but was not the problem....bad third party RAM chip that was only found after a new logic board had been installed). Now, with new battery in place, and still following my routine to get it conditioned from the start, everything working fine, with nearly 4 hours run time on battery.....as it is supposed to be. My thoughts are that there are some real QA problems with the batteries from the maker (Sony in many cases, but not all), and behaviors can be off normal schedule. In other words, the "smart" battery may not be so smart all the time. It is possible that leaving things plugged in all the time actually create some of the malfunctions. Apple does recommend all laptops to be run on battery for at least a few hours each week.....not to shutdown, but just to keep the circuitry between the battery chip and the computer charger in sync. Evidently that sync can get messed up when plugged in all the time.

LJ

P.S. As an aside to that, a lot of us were having similar charging issues with the batteries in the Leica M8 when it was first released. Even Leica did NOT recommend leaving batteries in the charger once they were fully charged.

 

[Guy Mancuso]

Guy,
This makes NO sense to me at all.
You get a bigger system without the nice portability of the 15 at lower performance and without the expandability of the MacPro.

The 17 is not really disk performance limited, it is CPU and memory limited.

Oh wait, am I repeating something somebody already said?


:ROTFL::ROTFL::ROTFL::ROTFL::ROTFL:

Yea you ding bats are not setting here looking at 1200 images to process by morning for a show and it is 10 pm already. I need better road gear. LOL

I love ya both you know that but I WANT SPEED.:ROTFL::ROTFL::ROTFL:

 

[Jack]

And you are working how far away from your studio (and that Mac Pro tower) right now? Total round-trip drive time at the speed limit -- as opposed to how fast you normally drive -- will suffice.



:ROTFL: :ROTFL: :ROTFL:

 

[Guy Mancuso]

LOL I know it is just easier to stay at the hotel. I want that 2.93 processor and bigger cache. Maybe just update the laptop when I have the money. First thing though is drop a second SSD in this one and run Raid O. At least I can get to a 160 gb hard drive , 80 is a touch small. If I move up I can at least take that with me. I will sell my 24 inch cinema though. To pay for that SSD Drive and mounting hardware.

 

[Terry]

LOL I know it is just easier to stay at the hotel. I want that 2.93 processor and bigger cache. Maybe just update the laptop when I have the money. First thing though is drop a second SSD in this one and run Raid O. At least I can get to a 160 gb hard drive , 80 is a touch small. If I move up I can at least take that with me. I will sell my 24 inch cinema though. To pay for that SSD Drive and mounting hardware.

You will miss that monitor.

 

[Guy Mancuso]

Not really when at shows they rent one for me for the weeks but at home your probably right. Sacrifice is my new middle name. LOL

 

[Oxide Blu]

... Apple guru postulated that the internal battery chip went haywire. If not that, then there is something else wrong on the logic board (which was replaced about 16 months ago, but was not the problem....bad third party RAM chip that was only found after a new logic board had been installed). Now, with new battery in place, and still following my routine to get it conditioned from the start ...

THAT'S an iApple problem! Yeah, follow iApple's advice. Never heard of anything remotely close to that with any other Li Ion battery application.

To test the individule cells there must be a way to isolate each cell inside of the battery. We're talking about some serious battery design for what is arguable a throw away part, e.g. not worth the NRC or manfg costs to implement. Now I'm curious, when I get back I'll look into what those iApple batts are all about.

Fwiw, nothing about a Li Ion battery requires "conditioning". Maybe it has something to do with keeping in line all of that funky iApple battery management logic stuff you were talking about. The whole idea of needing to run your computer on battery power for a few hrs a week sound like either iApple has some serious design issues, can't get their act together on how to charge a friggin' battery (doubt it), or someone wants to sell batteries -- reference what I said above about there being only so many 'cycles' in a battery's life before it dies.

As far as what I said about leaving a battery in a laptop when on AC, I don't think I have ever removed my battery from my Lenovo/IBM, spends most of its life on AC, battery has been in there about 3-years now and still supports the laptop for the spec'd time. Lenovo has a pretty good battery management scheme. I just checked the condition of my battery and it is rated Good+, consistent with the performance I am getting. This is after 3 years. And I can guarantee you there isn't a nickel's difference between the cells inside of your iApple battery and my Lenovo/IBM battery. It's all about how the battery charging is managed and keeping it on a float/maintenance charging scheme.

P.S. As an aside to that, a lot of us were having similar charging issues with the batteries in the Leica M8 when it was first released. Even Leica did NOT recommend leaving batteries in the charger once they were fully charged.

Computers have some intelligent battery management and charging schemes built into them. They are safe to leave Li Ion batteries in all of the time while on AC. Not all battery chargers are that way, especially the el cheapo wall warts that come with many cameras, MP3 players, and cell phones. Those chargers are marginal, at best, for managing a potential over-charge. Over charging a Li Ion battery is a huge safety issue -- think: FIRE! Never leave a cell phone or MP3 player plugged in and charging after the indicator says it is charged. The same goes for most camera batteries that rely on a wall wart charger. Remove then after they are charged. I'm thinking it's not a Leica issue, and it is not a battery issue; it is an el cheapo battery charger issue.

 

[DougDolde]

Back to the original question. Lloyd Chambers just posted a review of the Mini.

http://macperformanceguide.com/Reviews-MacMini.html

 

[Lars]

CPU L2 (or L3 for Nehalem) cache size is VITAL for image processing performance. This is part of the reason the previous-gen dual quad Xeon Mac Pro was so fast. So regardless of generation, look for a CPU with large cache. This could be a problem with the Mini, find out exactly which CPU it has.

If you decide to go with the new Nehalem Mac Pro - stay away from the budget model as it's quite limited WRT expansion, max 8 GB. So you're looking at some $3200+ for a starter.

 

[robmac]

That's the kind of analysis that makes LC's site so invaluable. Not just talking about expansion, etc, but trying it and reporting vs other configs.

 

[Terry]

Thanks for the Digillyod's Mini link. That is exactly what I was contemplating doing (base model + RAM + fast drive. Haven't made any decisions yet.

 

[Guy Mancuso]

CPU L2 (or L3 for Nehalem) cache size is VITAL for image processing performance. This is part of the reason the previous-gen dual quad Xeon Mac Pro was so fast. So regardless of generation, look for a CPU with large cache. This could be a problem with the Mini, find out exactly which CPU it has.

If you decide to go with the new Nehalem Mac Pro - stay away from the budget model as it's quite limited WRT expansion, max 8 GB. So you're looking at some $3200+ for a starter.

That is what i have been looking at is the new cache of the 15 and 17 inch L6 cache 2.93 1053 mhz. Kills my L4 cache. My laptop is 2.4 667 mhz and desktop 2.66 667 mhz both L4 cache.