I did pick up a MacBook on Friday, though I barely had time to unpack it and start setting it up before all hell broke loose. 🙂
Today I was able to do a little more set up and follow up on a few things I’d had questions about – one of which being the extra power adapter I picked up at the Apple Store1.
The MacBook uses a 60 Watt power adapter and the power adapter they sold me was actually the 85 Watt MacBook Pro power adapter. Despite reading that it was unlikely to cause any harm, I was a little hesitant to actually use the thing.
Today I placed a call to an EE friend of mine and he helped me find the confirmation that it is OK to use the 85W MacBook Pro power adapter with the MacBook.
Both power adapters have the input and output levels printed on them in small print. The 60W MacBook power adapter shows output levels of 16.5V – 3.65A. The 85W MacBook Pro adapter shows output levels of both 18.5V – 4.6A and 16.5V – 3.65A. There is no switch that I can see, so it must auto-sense the proper voltage.
This is particularly nice because it means I won’t have to buy another adapter when I get a MacBook Pro sometime in the future.
Hopefully this will post get picked up by the search engines and the information will be helpful to others with the same question.
- I really like being able to leave one plugged in at my desk, nicely threaded through my cable trays. [back]
I’ll second that – having two power adapters (or, n+1 adapters, where n is the number of desks you typically use your machine at with obscured power points) is a must.
Useful info too as I’m going to make the jump to a MBP or MB in the next month or so.
But the question is – did you buy a Black one 🙂 How does Windows run on it? Is a further write coming soon Alex?
I’d love to read the AlexKing review on the MacBook. I’ve been reading reviews that says it runs too hot. True? Not that big a deal? I’d like to hear your opinion.
I’ve got a bunch of draft “stubs” for MacBook posts. Hopefully once I recover from losing 2 days of work with the stupid new server config I’ll be able to get them posted. 🙂
Seb – Yep, I got the black one.
danithew – I’ll try to cover the heat issues I’ve experienced in one of the posts.
You have cable trays on your desk? What kind of nerd are you? Real nerds have them draping all down the back of the desk and pooling at your feet!
At work I solve the problem and make it much more convenient when I’m setting up a new laptop by running a power strip (through all the cable trays, if I had any) and leaving it on the back of the desk. Then I can take my power adapter with me, but it’s still easy to plug it in. When I flip open the laptop, you can’t even see the mess of cables coiled up behind it.
Thanks for the info, I had been wondering if it were possible to use them interchangably.
[…] Several folks have asked for my thoughts on the heat issues and battery life of the MacBook. Here they are… […]
Thanks alot! I really appreciate you posting this information – it DID get picked up by a search engine and I am incredibly grateful – it saves me a ton of hassle!
For those of you worried about heat issues, there is a utility called “smcFanControl” that I have installed on my Macbook. This utility also works with Macbook Pro. It changes the MINIMUM fan speed, and does NOT tinker with the automatic fan spin-up for when the processor gets hot. I set mine at about 2500rpm (instead of the default around 1000?) and have noticed barely any noise and the machine runs a LOT cooler. I’ve even got Parallels running most of the time and it’s not uncomfortable to run it on my lap.
As for “how does windows work?” It works fine. I use Parallels although we have machines using BootCamp at my work. I was extremely surprised how fast it boots on Core Duo processors. I seriously hit “reboot” in WinXP Pro yesterday and looked at my other computer, read a paragraph (about 10 sentences) and looked back at the Macbook and it was already done booted into XP Pro SP2. Sweet.
Lost my extra macbook adapter and I’ve been thinking about a macbook pro, so finding this post allowed me to make the decision to get a MBP adapter to keep my options open. Thanks!
Is this true the other way around? A lower voltage Macbook can be used with a Macbook Pro? Seems unlikely, but thought I would ask.
[…] – I spend 2 weeks in Italy. The local volleyball gym re-opens. I consider upgrading my laptop and do so. A burned up CPU forces an emergency web server move. FeedLounge experiences another outage of […]
I have a Macbook pro with the larger power adapter, and my wife has a regular Macbook. I charged the Macbook overnight with the Macbook Pro charger, and since then the Macbook battery no longer works. I’ve run through all the Apple Support site fixes without any luck. I don’t know if this is a fluke, or if there is a real compatibility issue (contrary to what this article is saying). I would suggest people procced with some caution when swapping these adapters – hopefully over time the compatibilty question will become clearer.
I’ve been using them together for almost a year now, no problems. There really is no compatibility question, just make sure you check the ratings as explained here to make sure they are compatible.
Thank you, Alex! This is just the information I was looking for. The Google search which brought me here was: “macbook using 85 watt adapter”. Thanks again!
i dont think it would hurt it. think of a desktop pc you build yourself. you can buy a 750 watt power supply, but if you’re just building a simple computer for your grandma with a slower processor, integrated graphics and only one hard disk it wont use the power supply to the full capacity.
its like both a old VW Bug and a BMW can go 65 mph on the freeway, but the Bug will be working a lot harder to do the same speed as the bwm easily does. just because theres POTENTIALLY more power available doesn’t mean it has to be used. so my guess is the macbook would just draw the 60w it needs from the macbook pro adapter and nothing would get damaged.
RE: Hopefully this will post get picked up by the search engines and the information will be helpful to others with the same question.
It certainly did, thanks a million for pointing this out!!
I had to fix MacBook Pro 1,1 the other day and I did not get the adapter with it …. I found MacBook 60W adapter and just pulled the battery out of the laptop to save power. Worked like charm 😉
laptop had only 256MBx2 ram!! I do not know how much power 1GB ram modules use and fixing OS bug dose not require much power from GPU
I think the power peak comes from charging battery and putting load on the RadeonX1600 graphic card
I also notched the battery pack is rated 60W so putting load on the computer while the battery is not installed should be ok 🙂
Thanks for the info.
My MBP’s power adapter has a frayed connector and I saw some smoke coming out of it the other day. Since I am all out of my one year warranty, the apple store won’t replace it. Given what you have explained about the variable output on the MBP’s power adapter, it would make sense to assume the MBP uses the higher power output, while the MB can use the lower one. Hence, what do you think would happen if it were to be the other way round i.e. if I were to use my friend’s Macbook Power adapter w/ my MBPro?
Good looking out. I found this on Googl and it is very helpful. For the guy with the wife whose battery is busted, looks like a coincidence. As for the Beetle/BMW analogy and ‘just because more power is available doesn’t mean it has to be used”, I think there are some flaws inthe logic. But, if you believe this to be true, you can probably get some really fast charge times if you modify the 220V line on your clothes drier to plug in your macBook Pro. The Adobe suite is expensive as hell, but if you hook up a 220 line to the computer, it comes with free Flash!
Glad to find this discussion. I have a MB. My friend’s MBP’s power adapter has a frayed connector too and is really erratic. So in the interim she has been using my MB 60 W charger with the battery in and all (using OS X and XP). The only difference is that it charges slowly. It seems all the Apple stores are out of stock of 85W chargers since they just updated the charger and it hasn’t yet shipped to stores. Now that the MBP’s charger is the same size as the MB charger I think I would probably get the MBP charger as it can charge both MB and MBPs quickly and they both cost the same. Does anyone know if charging a MB w/ a MBP’s charger is faster?
I’ve been using a MB 60w charger on my MB pro for some time and I’ve noticed some interesting changes – The battery does take longer to charge, BUT it lasts much, much longer. And after charging with the 60w, the fans don’t turn on and the whole unit runs cooler. The whole system seems more stable in fact. Strange but true. Anyone else noticed this?
i have been charging my MBP with my MB adapter for about a week (i didn’t realize they were different) and it has been crashing a lot. is this just a coincidence?
also, is it possible to get one of the old 85w chargers? i really need one and the new ones are not in stock anywhere!
Hey, thanks a lot for the info. It was the first page google popped up.
Thanks for the info. I have an MBP and my girlfriend has a MacBook. About a minute ago, she plugged my power adapter into her MacBook, and I just had to google to make sure.
So thanks a lot. You’ve done good. 🙂
I am currently typing from my macbook….with my flatmate’s macbook pro adapter….my worries have gone away. Thanks Alex! Hello from Rome, Italy!
Hi to everybody, thanks for the info. I have the same doubts of you. My MBP adapter reports 16.5-18.5V 4.6A Max so I think it works at a Maximum output. Maybe the MB cannot change the input levels so it could be damaged by the too high input. Maybe the battery can be overpowered and will break. But if they are not compatible, why Apple didn’t change the MagSafe plug in order to avoid confusion?
Viceversa, MB Adapter has too low output for the MBP to charge and work at the same time at it could crash. Maybe it is ok just to charge the battery before working on it.
Netnemo: I just bought one of the 16.5-18.5V 4.6A Max 85W MBP adapters. The box says “compatible only with MacBook Pro and MacBook computers.” I trust Apple’s labeling and would have no reservation using it with a MacBook.
Thanks, that’s what I was ‘googling’ for.
I am a big advocate of standardizing things so that people do not have to constantly wonder, “Will this work with that?”
Right now I am trying to get a consensus on what the standard power supply should be. Would love to get your opinion on this.
I have an MBP & bought a macbook off of ebay the other day. When it arrived I eyeballed the magsafe connector and plugged it into the mbp power adapter laying there on my desk. Green light, no smoke, happy guy. Later I noticed a black “x” in the macbook battery icon. Couldn’t make it go away. ‘Book won’t read the battery no matter what I do. No charge indicator lights will light up on the bottom of the battery case. Ebayer swears it was working fine when shipped & I believe them. Machine is near new, original owner, credible seller. It’s under warranty so I’ll call apple and play dumb: “It just doesn’t work. I dunno why.” Nothing on this site would let me tell Apple that I did it because they said it was OK. Will try to remember to post follow-up. My opinion at this point is that I would not, given an option, plug a MBP adapter into my MB.
Or you could learn about these things and discover that you can use a more powerful adapter for a machine that ships with a less powerful adapter, but not vice versa.
MacBook Air = 45w
MacBook = 60w
MacBook Pro = 85w
Hi, came back from being out today to find my mbp down and without power. I plugged in my adaptor in and it did not charge or turn on.. I just checked and realised I was using my husbands mbooks adaptor.. I have just swapped it around for the correct adaptor and bingo the battery looks like its charging. I havent tried to switch it on yet, fingers crossed it works. I will keep you all posted. My advice.. use the correct adaptor for the mac you buy. Thanks
UPDATE: My MBP booted up, but first went to a washed out gray page.?? Then booted up as normal.. and the battery started to charge in the menu bar. I’m just glad its booted up and seems ok….Yes good advice Alex, you are exactly right! I have learned from this, I hope others do too. Glad I found this blog, its great. Cheers
[…] this post by Alex King allayed my fears. It seems that the 85W Magsafe Adapter reads output levels of both […]
Is it OK, then, to use the MacBook Pro 85w Power Adapter on a MacBook Air (whose adaptor is usually 45w)?
Hello all. I know I am not a very credible source, but I work for Apple. At the Genius Bar we use 85w adaptors across the board. We have never had a problem whatsoever using the 85w with the normal Macbooks (all generations).
If you have a problem with this, definitely call AppleCare…
I have a Macbook Pro, and wanted to get some extra cords.
I know it seems silly, but I’ve been messing with this one cord for much too long – over a year.
Every morning I fish it out of the tangle of cord behind my desk at home, wind it up, take it to work, unwind it and plug it in behind my desk. And then, I do it again at the end of the work day. Plus, if I take it to a cafe, or a friends house, I have to do it again.
My plan is to have a cord at home, a cord at work, and a cord in my backpack. Then I’m covered.
Anyway, I saw several cords; 60w, 85w and was figuring out which one was what I needed and saw this blog.
Thanks for the info.
Thanks for this! I happen to have an TWO EXTRA 85watt chargers now because the MBP crashed and burned, and is useless now, and since I had TWO 85watts replaced under warranty I decided to buy a backup just in case it happened again (I had to wait a week for each replacement).
Alex, are u going to investigate the MBP Nvidea snafu where hundreds of MBPs are failing as Nvidea stock plummits? Cheers,
I just called Apple Care to get an official answer. I asked specifically about use the 85 watt adapter with the Macbook Air. Of course, they said that it’s not recommended, and that it would however probably work, but the wattage difference could be too much for the Air to handle. They also said that any damage that might occur would not be covered under the hardware warranty, so to be careful.
For reference the CE label on the 45w Air Adapter says: Input: AC 100-240V 1.0A, Output: DC 14.5V 3.1A
I think that for the Air, the power supply from an MBP is too much, and might overload the circuits.
it got picked up by google and just helped me a lot! thank you!
So can I use a Macbook power supply for my Macbook Pro?
I’m guessing not… sounds like only the Pro power supply can be used for both versions of the computer.
There are only 2 wires going from the adapter body to the plug that goes into the laptop. There is some circuitry on the plug… a small chip and 2 leds…
I dont know how the adapter could sense what power setting to use, either the laptop will cut the circuit when it gets the wrong voltage, and the adapter will try another power setting… or data is exchanged between the adapter and the plug, or between the adapter and the laptop through encoding power impulses…
Just wanted to say thanks for posting the info. My wife and I share power supplies with mine being a MBP and her’s a MB, I wanted to confirm that we don’t blow up each others computers if we use the wrong power supply.
Thanks alot! I was wondering because I left my MacBook adapter at home and I need to use my laptop while I’m away so I have to buy a new one. The MacBook Pro adapter is cheaper than then the 60W Macbook adapter. Very useful info thank you!
I have a MBP and my husband has a MB. We got our cords mixed up a couple of weeks ago and had not noticed the difference in size or wattage until my MBP started having problems. It was really slow and never fully charged. Also no green or orange light when my MBP was plugged in. His machine was working fine. I discovered I was using the 60 Watt cord and now I find that my MBP will not fully charge. We’ve switched back but that doesn’t help. No matter how long it’s plugged in with it’s 85 W cord I can’t get more than a 96% charge. I think the 60 W cord wasn’t giving me sufficient power. I had used it for about two weeks before I figured out what was wrong.
The easiest answer is this.
This is an age-old question that has been confirmed and down in the record books. People had the same issues/questions for the PowerBook G4s. 45W adapter or 65W adapter?
The Titanium PowerBook G4 and the 12-inch PowerBook G4 (as well as iBook G4s) all used 45W adapters. The 15-inch and 17-inch PowerBooks used 65W adapters.
At the Apple Store, they stopped carrying the 45W adapter and replaced it with the 65W adapter which was compatible with all PowerBook G4s, whether they used the 65W or 45W adapter in the first place.
The ones rated for 45W, such as the 12-inch PowerBook, would only use as much as it needed from the 65W-rated supply. On the contrary, using a 45W adapter with a high-end machine, such as the 15-inch and 17-inch models (although it worked) was not recommended as it could possibly damage your machine. (Still, people used it anyway).
One example was the battery. Using a 45W adapter to charge a 15-inch PowerBook’s battery took much longer than when connected to the 65W one. Also, since it was rated lower but needed higher specs, it would put strain on the machine as it needed to work harder to get the juice it needed.
As for the MacBook and MacBook Pro equation, the same falls true. The only thing I can’t confirm is whether it will damage a MacBook Pro to use a 60W (or even the 45W made for the MacBook Air). I’ve read on the Apple Discussions forums that a 60W can run a MacBook Pro, but it will not charge the battery. Has to run plugged in all the time.
So if you had a 60W adapter at work, and your 85W as your carry all then you might be fine. Only thing? Both adapters cost the same price, so it really doesn’t matter. Best to get the one designed for your machine. (Unless of course, you were trying to save money and found a 60W adapter cheaper–say, on eBay or Craigslist–than a new 85W one).
Thanks for this. I had a new MPB adapter I had for my MPB, but recently traded it in and got a new MB. I left my 60 at work and have an 85 at home and so far so good.
It did get picked up by a search engine! Thanks for the Info
I have a mbp, and have been taking it to work where I use a mb, and using the 60W charger between them. Since then I’ve noticed a CRAZY drop in my mbp battery life, and it’s now about 30% of max, and I haven’t been using the 60W charger for about a month. I’m going to try cycling my battery to see if it helps, but I’m afraid I’ll end up shelling out the $200 Canadian for the new battery
Cheers guys you’ve collectively answered my questions!
You can’t use pro chargers with normal macbooks, pro chargers are between 75 and 85 watts, normal macbooks run bettween 45 and 60 watts!
Yes you can, that is the whole point of this post. It is confirmed by the device specs as noted in the post.
Thanks a bunch!
Hey thanks for this.
I’m about to change from a 15″ to a 13″ MBP, and I have an extra 85W adapter. The 13″ ships with a 60W adapter. I didn’t want to have to buy a whole new 60W adapter just because I’m switching to a smaller MBP, you know?
lol, I just came back from a trip with my new 15 inch macbook pro, and left the charger behind. I decided to make absolutely sure that my old 60 watt macbook charger would work fine (only concerned because I love the new 8 hour battery soooo much!), when I realised that I had mixed up my chargers, and that the charger that I left on said trip is actually the 60 watt, and has been charging my computer for a month! I think that my lack of issues (or really any noticable difference at all), serves to prove that mixing and matching chargers is fine, at least for a month!!
Useful info! got exactly the info that i need in this article of yours when i googled it! Thank you! still relevant til today! just got a new 13in macbook pro and want to use my old magsafe (85watt – from the first generation macbook pro!) adapter at the office, now that i know it is safe, i’m very happy not having to lug my adapter around with me from home to office 🙂
Just wanted to chime in to say I have similar experiences. I have an MBP at work, wife has an MB. I’ve been charging the MBP at home using her MB charger for around a year. We hadn’t noticed any ill effects as such, frankly we were not even aware that there could be a problem; However, in retrospect I can now affirm that doing this does **degrade** the battery life of the MBP significantly; my battery now lasts less than an hour. Also, we have recently noticed that the adapter and thin Magsafe lead run **very** hot to the touch, and have started to worry. I will be looking at buying an extra MBP charger for home use, and thinking about buying a new battery. I wish this information was more widespread so I wouldn’t have ruined the battery…
“Hopefully this will post get picked up by the search engines and the information will be helpful to others with the same question.”
just what it did. Thank you!
Same as Rasmus Keldorff for me…
I was using my girlfriend 60W battery on my MBP… My battery started to charge only 96% and lasts (at best) 1 hour… after that 30min… 20min and now Its no longer working…
So, please, pay attention here.
DO NOT EVER CHARGE YOUR MACBOOK PRO WITH A 60W CHARGER 😉
I just purchased a used macbook pro 13.3 “with the 85W magsafe charger”. From other info,this can only be used with the 15 and 17″. I have read in this blog that the 85W are cutting the life of the battery? Should I buy a 60W,soon as possible? Also, I am new to mac and would appreciate recommendations of other good info/support sites.Thanks.
Exact same situation here–even down to the girlfriend having a MB!
I found this forum this morning, because my battery-very weak these days like yours– died last night, and this morning I couldn’t charge it at all. The 60W would charge my MBP in the past, but it seems I crossed a line last night.
Of course, all electronic appliances always command you to only use the original adapter that came with them. However, yes, it is definitely NOT widespread knowledge, and the identical appearance of MB and MBP chargers, as well as the general universally-compatible, plug&play culture of Mac all combines into a recipe for MBP battery disaster.
USERS BE WARNED!
Thanks this is very helpfull!!
I think Apple should take more of the blame. They put out different machines with different electrical needs and package them with power cords that look identical unless you read the fine print with a magnifying glass. A similar case could be made about iPads and iPhones requiring 10 and 5 volts of input respectively but using interchangable cords. When asked, Apple covers its bases by telling you not to switch the cords. But the confusion forces users to burn out their batteries prematurely and therefore need to buy more Apple products. Disgusting.
I have a 15 inch Mac Book Pro 2.4 ghz i5 and recently one of the kids got a 13 inch mac book pro core 2 duo, I accidentially brought the wrong brick to work and noticed that intermittently it would not charge using the 15inch power cord that i leave at work. This morning i have noticed that the brick from the 13 inch on the cord from the 15 inch plugged into the 13 inch macbook pro will not charge at all, the brick from the 13 inch on a cord from the 15 inch has intermittent problems when plugged into the 15 inch computer and that the cord and brick from the 15 inch works fine in the 13inch if used together shees i have confused myself so it seems that brick and cord must be used together to avoid compatibility issues
Killed a 45w Macbook Air adapter by using it to also power a 15inch Mac Book Pro, worked for a while obviously overloaded. Silly me! Thought Appleland would be even better than the PC world where if the plug fits, it works!
I am quite experienced in electronics and computers but not apple products! Never had this problem with pc’s or mobile phones!
Check out Ebay for good cheap replacements for around $25!
Power adapters are not an area I’d advise “cheaping out” in.
Normally using the Power adapter 85W with any Macbook using from 45- 65W should not be a problem and will work supplying the necessary power that are demanding the System Management Controller (SMC), But at the opposite way you should not use the 45-65W in any Macbook or macbook Pro thats need the 85W, in this case the computer will work but after a time this will cause problem with the battery and even with the main board. because the adapter will not supply the necessary power needs the for System Management Controller (SMC)
This is exactly i want to say ” Power adapters for Intel-based Apple portables are available in 45W, 60W, and 85W varieties. Although you should always use the proper wattage adapter for your Apple portable, you can use an adapter of a higher wattage without issue.
For instance If you have a MacBook (13-inch Late 2009) that normally uses a 60W adapter, you can also use an 85W adapter with that computer. You would not use a 45W adapter with that computer; it would not provide enough power for that MacBook. Using an adapter of higher wattage than the adapter that came with the computer will not cause the computer to charge more quickly or otherwise operate any differently than using the adapter that came with the computer.
I understand that is what Apple says, but my experience has been different.
Your mileage may vary.
It WAS picked up by a search engine and found to be very helpful!