Imac mid 2011 confusing ram installation

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I'm confused by the description in the apple support notice(http://support.apple.com/kb/HT1423):

"i5 and i7 Quad Core iMac computers come with both top memory slots populated. These computers will not start up if only a single DIMM is installed in any bottom slot; these computers should operate normally with a single DIMM installed in any top slot."

They are populated with 2-2gig chips. But if I want to add a 4 gig chip, the implication is that I cannot put it in one of theopen bottom slots. So to make sure that I don't have only one chip in the bottom slot, I would need to move one of the 2 gig chips that were pre installed, into a bottom slot to go along with the 4 gig chip I'm adding.

Is this correct??
 

chscag

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Your link is broken or doesn't work but I found the article anyway. My understanding is they're talking about using a single module in the bottom slot. In other words, nothing in the top slots. Then, the machine will refuse to boot. Unless I'm reading it wrong, it seems to me you can have both 2 GB modules in the top slot and one 4 GB in the bottom slot for a total of 8 GB. As long as the top slots are populated, you can have a single module in the bottom slot and the machine should boot OK.

Also, Apple says the Mid 2011 iMacs have a maximum capacity of 16 GB whereas OWC says you can actually put in 32 GB. That would be 4 x 8 GB modules. Very expensive though!
 

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^^^^

What chscag said... :) In other words - populate from the top down where the 'top' in this case - are the slots closest to the back of the iMac. Oh - and don't use a screwdriver to push the RAM modules in like a certain forum member did. :Blushing:
 
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Maybe I wasn't clear. I don't need instruction about how to put memory in. I've taken two powerbooks, and a mac book pro apart and replaced various parts and hard drives as well as putting in memory. That's not the issue.

There are four slots for the memory. My imac has the top two populated with two 2-gig Ram chips. The bottom slots are empty.

The apple support bulletin clearly states that it won't start up if I only put one chip in the two bottom slots. Of course I could buy another 4 gig chip, but not knowing this upfront I did not do so. Since I am now working on my old powerbook 800, as my macbook pro developed the black screen of death, I am chomping at the bit to get back into my new imac when it comes. But clearly from the bulletin, if I just put a 4 gig in ONE of the empty bottom slots, it won't start up.

So this means I have to move one of the two gig ram chips to the bottom slot, and put the 4 gig ram chim in the other bottom slot so that I have two 2- chips in the bottom, and one chip in the top(that is a 2 and a 4 at the bottom, and a 4 at the top.

Right?
 

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Maybe I wasn't clear. I don't need instruction about how to put memory in. I've taken two powerbooks, and a mac book pro apart and replaced various parts and hard drives as well as putting in memory. That's not the issue.

There are four slots for the memory. My imac has the top two populated with two 2-gig Ram chips. The bottom slots are empty.

The apple support bulletin clearly states that it won't start up if I only put one chip in the two bottom slots. Of course I could buy another 4 gig chip, but not knowing this upfront I did not do so. Since I am now working on my old powerbook 800, as my macbook pro developed the black screen of death, I am chomping at the bit to get back into my new imac when it comes. But clearly from the bulletin, if I just put a 4 gig in ONE of the empty bottom slots, it won't start up.

So this means I have to move one of the two gig ram chips to the bottom slot, and put the 4 gig ram chim in the other bottom slot so that I have two 2- chips in the bottom, and one chip in the top(that is a 2 and a 4 at the bottom, and a 4 at the top.

Right?

Ok. First - the RAM installation mention was really tongue in cheek - hence the :Blushing:. Rereading that KB - scratch the previous terminology. I'll have to pull out my iMac manual - but that seems reverse terminology from what I recall - albeit - referring to the same slots, and now I'm questioning my own memory. I had 3 DIMMs in there for a period of time - and I'm fairly sure it was in fact - as you say - I had the single DIMM in the top slot - but it was a few months ago. At any rate - if you get it wrong -you'll know immediately - it'll chime at you - and then you can change it.
 
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On the Mid 2011 macs

Apparently what needs to be done is this(since I only bought one 4 gig ram chip, and I'd like to get started with it):

Move the two initially supplied 2 gig ram chips from the top two slots to the bottom two slots. Put the new 4 gig ram chip in the one top slot.

I've ordered a second 4 gig ram chip to also go in the top slot when it comes in, but in the mean time this works. Also apparently, you have to have only the same size ram in both slots side by side/bottom-top, this means that you can have a total of 4, 8 , 12 or 16 gigs, but not 2, 6, 10, or 14 gigs(unless you were using 2- 1 gig chips in one of the bottom or top slots).
 
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Wrong...^ Chscag nailed your answer earlier.
 
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Well.... Chscag seems to have a view point in conflict with the actual Apple Support page. The support document says that you must have two chips in the bottom slot, and you can have one chip in the top slot. If you have no chips in the bottom slot, that is fine, but you cannot have only one chip in the bottom slot. New macs come with no chips in the bottom slot, only chips in the top slot. If you want to add two chip, not a problem. But if you only want to add one chip, then you must move the two chips that apple puts in.

After reading the support brief again several times its obvious. Now this is the the mid 2011 i5 and i7 imacs, only. Apparently it has to do with the 64 bit operation and the quad design of the cpu.
 
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Well.... Chscag seems to have a view point in conflict with the actual Apple Support page. The support document says that you must have two chips in the bottom slot, and you can have one chip in the top slot. If you have no chips in the bottom slot, that is fine, but you cannot have only one chip in the bottom slot. New macs come with no chips in the bottom slot, only chips in the top slot. If you want to add two chip, not a problem. But if you only want to add one chip, then you must move the two chips that apple puts in.

After reading the support brief again several times its obvious. Now this is the the mid 2011 i5 and i7 imacs, only. Apparently it has to do with the 64 bit operation and the quad design of the cpu.

I know this is from years ago, but I wanted to see if this solution was viable -- with the two original chips and a single 4GB chip in the top slot. I've only purchased one 4GB chip for my mid-2011 machine!
 
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hi golden this is an old thread but it will work


and if u want you can then get a further 4GB chip to go in the empty slot
 

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