3GB MacBook memory processor overload

July 23, 2010 10:47 AM

Apple support told my mom 3GB of memory in a Late 2006 MacBook (1.83GHz C2D, Snow Leopard) could overload the processor. What could they have meant by that?

Apple officially lists it as supporting 2GB of memory but when that wasn't proving to be enough for my mom's uses (she basically keeps all her applications open always) I installed 3GB (1GB+2GB) after researching to find it would work. Low End Mac confirms the 3GB option, as do various online discussions. It's been a while since I looked into it but I think the 3GB limit (or technically ~3.25GB if you installed 2+2) is due to the 32-bit address space limitation.

She'd been happily running 3GB for a couple years until April when her computer had to be sent to Apple for a logic board replacement (yay! for Applecare) from an unrelated issue: the USB ports were working intermittently. I don't know if there was a physical problem with the ports or if it was something else like the USB controller.

When she got the machine back it was running very slowly, although I didn't know this until last weekend when I was in town and she asked me about it. Checked the machine and found it had 512MB of RAM installed, what her model originally shipped with, and that she had some crazy high Page Out listed in the Activity Monitor. She talked to her local Mac shop who had her call Apple. The guy she talked to there said it was listed as having 3GB when it arrived at Apple and they normally return what comes with the computer but it wasn't documented that they had done so. He asks if she wants 2GB or 3GB sent and "that they recommend 2GB because 3GB could overload the processor" (quoting from my mom). She says send 3GB.

I've been trying to figure out what the Apple guy could have meant. I know that unbalanced RAM (like 2+1 vs 1+1 or 2+2) can hurt performance under certain applications, maybe graphics intensive ones. But I can't figure out what overloading the processor could mean nor why 3GB memory could do that. The quote is as close to verbatim as my mom recalls. I'd like her to be able to continue using 3GB if it's a non-issue but I'd hate to have it cause a problem if it can do so.

posted by 6550 to computers & internet (11 answers total)

I'm pretty sure what they mean by that is "2GB is cheaper for us to send to you than 3GB so we don't really want to do it so we'll make up something plausibly scary sounding to get you to let us steal some of the RAM you sent to us and we didn't return."
posted by brainmouse at 10:51 AM on July 23, 2010 [6 favorites]

This is just blatantly untrue. Sometimes Apple makes me want to pull my hair out. Along with the lies, they act so over the top diplomatic at times that it makes them look like a sleazy company.

So in short, they were lying.
posted by Atlantic at 10:54 AM on July 23, 2010 [1 favorite]

He's talking twaddle to try and cover a mistake. It's sometimes the case that paired RAM modules can be better than simply having more memory overall, but this only in specific use cases (as the link mentions). 3GB is a-ok. It's certainly not going to damage the machine in any way.

(On a similar note, a friend of mine was told by an Apple authorised reseller that he couldn't put a hard drive bigger than 320GB in his MacBook Pro. When he asked why, he was told that if he did, ‘the machine may explode’. I wish this was a joke!)
posted by jaffacakerhubarb at 10:57 AM on July 23, 2010 [1 favorite]

When he asked why, he was told that if he did, ‘the machine may explode’.

To be fair, this is tenuously true. It's just that it may explode with or without the >320GB drive. :)

OP, I can think of no reason whatsoever for such a statement from the Apple rep. Either he misspoke, or was trying to dissuade you from the extra GB of RAM purely to minimize the incident of their not sending you enough back in the first place.

Okay, I can think of one tiny reason--maybe he meant to say that using that much RAM would increase the power consumption of the laptop as a whole? But that doesn't really make any more sense--to be clear, while technically using larger RAM might increase power consumption and heat generation by some tiny fraction, it wouldn't have any real-world effect, catastrophic or otherwise.
posted by Phyltre at 11:13 AM on July 23, 2010

When you do something outside of the official spec you get reactions like this from the tech support people, who don't really know what would happen but don't want to (or have to) deal with it and don't care. So I wouldn't take that as the official line on why the official spec for that machine is limited to 2GB, but it doesn't mean there isn't a reason. IIRC (I had one of these) there was some particular reason due to the shared vram (in combination with a terrible intel graphics chip) not to have unbalanced memory configurations.
posted by advil at 11:41 AM on July 23, 2010 [1 favorite]

My understanding is that replacing the RAM yourself voids the Applecare warranty. The 3GB move might have been enough where they saw it, changed it out to see if it would work, and then didn't want to put it back in when they got it working.

Also, Apple is being stupid about this. I've been an Apple user since the early 90s but am disliking them more and more.
posted by jeff-o-matic at 11:42 AM on July 23, 2010

When you do something outside of the official spec you get reactions like this from the tech support people

Just to be clear I don't mean this as a comment about apple specifically -- you will get reactions like this from official tech support any time you take a laptop that the manufacturer has claimed doesn't support >2GB memory, and add >2GB memory. Also, replacing RAM on a mac does not void the warranty.
posted by advil at 11:45 AM on July 23, 2010

My understanding is that replacing the RAM yourself voids the Applecare warranty.

Not so. The warranty doesn't cover third-party RAM, for obvious reasons, and there are word-of-mouth recommendations to take out your upgraded RAM and reinstall the original stuff before you send it off, but I've had send-return service from Applecare with third-party RAM installed. (Admittedly, it was for a buggered hard drive, not a logic board, but there was never any question that the upgraded RAM might be an issue.)

My guess is that the support techs looked at the spec from the original purchase order and rebuilt it to that spec. The 3GB config for MacBooks of that vintage is non-standard and unsupported -- my late 2007 MacBook officially tops out at 2GB, though has been tested with 3GB -- and my guess is that the support guys don't want to go on record doing something against the official line on RAM limits.
posted by holgate at 12:37 PM on July 23, 2010

My understanding is that replacing the RAM yourself voids the Applecare warranty.

According to two apple 'operatives' and my universities' IT dept this is not true. I checked several times regarding this.
posted by a womble is an active kind of sloth at 12:39 PM on July 23, 2010

Yeah, they're lying. I've also had friends get told that installing non-Apple-brand memory would cause the machine to explode.

Someone probably removed your aftermarket RAM as part of the logic board replacement process, forgot to reinstall it (or put in some Apple modules for test purposes and didn't swap them out), and now the tech is CMAing.

In the future, before you send an Apple (or any other brand, really) laptop off for hardware service, it's probably a good idea to pull any easily-accessible aftermarket modifications out of it, and get it back to a 'stock' configuration. This is not the first time I've heard about someone losing their RAM as a result of service. Big aftermarket hard drives can disappear too. (Though in fairness that wasn't Apple, in the case I know of.)
posted by Kadin2048 at 12:51 PM on July 23, 2010

Thanks everybody. I won't worry about it further. The situations in jaffacake's link that benefited from paired RAM I don't think are ones my mom is ever likely to run in to. She doesn't really do much that is processor or gpu heavy, just keeps all the programs she uses open at most times.
posted by 6550 at 5:50 PM on July 23, 2010