Problem with 16GB on 2010 iMac 27" i5 & i7.

This is an interesting thought. Keep us posted on the progress, if it really keeps on working.
If it does, I will give my 16 G OWC ram another chance while changing to another browser, even though I have no idea as to why.


peterwillem

Interesting, I was using Safari when reading the local news site this morning when my 27" iMac i7 just shutdown (16GB Ram from OWC).

If a machine is shutting down, producing odd screen results, or even hard freezing, then the issue is a hardware issue, not Safari. I know some get the beach ball, which could be software.

If you have a spare drive, you can install the OS there and test it out. I did, and my machine still powers off, on command.

It may not be RAM, but something else with the hardware. I wasn't convinced of this myself, but I've read too much in other forums that made me realize that much of what I read in this thread is a hardware issue. You change your RAM configuration and it works? It's a hardware issue. I took my machine in last night, and the store was more interested in replacing my system than I was. (Unfortunately, they did not carry my model.)

Here's what an Adobe developer said about my issue. He read this thread last night before he made this reply:

"It's possible that all of them have a timing problem with the motherboard, or a power draw that exceeds the motherboard design.

They could be on the edge of termination resistance and causing problems as well (all 4 are needed to push it over).

But my guess is a power draw issue -- and that could be a fault in the RAM, or a motherboard that isn't supplying enough power (even a single bad decoupling cap could do it)."

I agree with you on the hardware issue. The Safari-other browser solution was to simple to be true.
So if I read and understand your post correctly you and/or the Adobe guy are saying that:

Apple ram, Samsung factory and transcend ram are drawing less power from the mobo than all the other rams , who are causing the shutdowns.
I don't think it is likely that the various mobo's of the people ,whom are having these problems, are not supplying enough power. They are spread out world wide and have all the same type of iMacs. That would be to much of a coincidence.

peterwillem

Good question. I'm not certain of the answer. The Adobe developer seemed fairly knowledgable. As he said, I don't think we can really know unless you can measure it as it occurs. I worked for Novell years ago. Our developers did not usually have success in correcting issues if they could not reproduce and observe it. The same would apply to hardware.

Given this is an issue worldwide, then it's likely a system issue, and not one with power regulation.

Others speculated wildly in the Photoshop forum based on issues they had, but we know from our results that it's the 16GB combination that triggers it, as well as a few other odd combinations.

Any positive or negative feedback from those with Samsung, or Transcend (Hynix/Micron) RAM?

Sorry for the additional post, but I just got off the phone with OWC. The technical manager says they have received returned RAM and could not confirm issues with the same model iMac. They "ran tests". But some in the forum, including myself, have ran tests. The memory checks out okay. If this is an Apple issue, the memory will pass tests, and may likely pass them in a problematic machine.

However, given the rate of returns of OWC RAM, I don't want to take the risk of buying and then being stuck with RAM that may not perform weeks down the road. Even if it's not their issue.

I'm going to return my OWC RAM and see what others have to say about the Samsung Factory and Transcend memory.

This is what I have in my mac. Works great, no issues. Under $100 for 1 4GB stick.

http://www.jr.com/crucial/pe/CRT_51264BC1067/

I have done all the tests (AHT; Rember test recomended by OWC) and other things the said on their website concerning memory problems. And all tests showed that the ram was ok.
Except when you use it in a 16 G setup. I asked OWC if they have tested their ram and they replied that all the ram were tested before leaving their shop.
Than I asked if I could change the OWC ram for Samsung factorry ram(which they sell as well).
On that question I never got an answer. Phoning them is for me a bit difficult living in Holland.
So for now I am hoping that a solution will occur and meanwhile use less ram.
Buying Samsung ram is an option, but only when this particular ram is obtainable in Holland or Europe.
I am fed up with all the hassle of transportation costs,import duties, VAT etc.


peterwillem

Yeah with only 4 G my OWC ram works perfectly too. Try 16 G!

peterwillem

The shipping, VAT, and overpriced merchandise in the EU is crazy. Those in the UK probably see the worst of it.

When I worked in Oslo, I was shocked at the prices, and the taxes. My Nordic colleagues couldn't believe how little taxes I paid.

When I called Apple, they were not aware of the problem. The indicated that this would be a much bigger issue if this were a design or manufacturing issue. I disagree, as they told me the same thing with the ATI video issue on my 3-year-old iMac, and with the Macbook Pro NVidia soldering issue.

I asked for a replacement, given what the store had said, and the 2nd level tech was unwilling to process it and give me a "free machine" when my computer was 16, not 14 days old. In fact, I haven't even had it for 14 days.

I encourage everyone with this issue to call Apple and register their complains/dissatisfaction.

More to follow . . .

I totally agree with you on all counts. Though I did not ask for a replacement. I have mine for 2 months now. Apple care said that I should use Apple ram which causes no problems. And from their point of view they are right. As an individual you are more or less powerless against a multi national.
But from marketing/name viewpoint they definitely should take action on this, because the list of plaintiffs is still growing.
I wonder how many if any apple ceo's are reading these forums and if they do something about these kind of problems. I do recall the screen flickering issue.

peterwillem

I've been the rounds. First, the corporate Apple rep I spoke with says he'll do what he can do to get a new machine. I also tried contacting the Apple Store. The Apple genius did not document my visit for whatever reason, but their management said they'd get some comments entered. It sounds like they enter comments when they need to take action, and I told them last night I would address the issue myself. Then I saw this thread.

The store could not issue a refund or replacement on the machine because it came from the online store. So in both cases, I was going to have to wait for the online store.

The manager proposed a unique solution. He offered to sell me the RAM for what I paid to OWC. With tax, it's still $40 more, but well worth making this headache go away. I'm leery about the reports of Apple RAM failing as well, but this solution gives me three things: 1) I saw the very same modules work for me last night, 2) Our corporate rep sells more of these with 16GB preloaded than not (corporate sales), 3) if there is an issue, Apple can't claim it's a 3rd party. Apple also wins because they (hopefully) don't get a machine sent back.

However, given the reports in this forum, I hope I'm not swapping a repeatable issue with an intermittent one.

This is just a small update on my current status.

So a few weeks ago I received new RAM from OWC (RMA'd). It ran fine for about 7-8 days and then crashed 4 times in two days.

My case has been on-going with the Apple engineers for some time now. After reviewing some of my system logs they told me not to use a custom name for my primary HDD and to rename it back to "Macintosh HD" (renaming any other HDDs is not a problem). They claim that Adobe Flash has known issues if you rename your primary boot HDD. I'm not sure how that has anything to do with using 16GB or RAM, but I'm willing to try anything. So far since I've renamed it back to "Macintosh HD" I haven't had any issues for at least 4 days, but I'm not holding my breath on this one (they weren't too sure either, but they want to eliminate it as a possible culprit, so I'm game).

Just out of curiosity, has anyone else who has renamed their primary HD been having this same issue?

--
In case anyone is interested, the Apple engineers have been following the below threads I gave them last month:
http://discussions.apple.com/thread.jspa?threadID=2567907 (this one)
http://discussions.apple.com/thread.jspa?threadID=2588800
http://discussions.apple.com/thread.jspa?threadID=2560826
http://discussions.apple.com/thread.jspa?threadID=2548180

I think the suggestions are just an unwitting diversion. I don't have Flash installed on my test drive, but I do have Photoshop installed, which repeatedly triggers a crash.

I'd suggest dusting off a 100GB drive or more and install Mac OS and see where it takes you. I have renamed my drive, but my test drive is named Macintosh HD. It fails on both.

What do they see in the log that's the issue? And do you get hangs or crashes. If you see a crash, you may not see anything in the log, as in my case.

I never changed the names my iMac has given my two disks. Macintosh HD (my SSD disk) and Macintosh HD2 ( my 1 tb hdd). And I have these problems almost from the start. Though I have to say in the beginning it took several days before it happened , later only a couple of hours.
I followed the advise of Apple Care (Apple online store) and did a complete new system install erasing the ssd. I did a lot more which all can be read in my thread about this issue.
So I don't think the name changing has anything to do with this.

peterwillem