iMac -- RAM Upgrade

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Good Afternoon,

I'm new to the forum, and wondered if anyone could help me.

I recently purchased a 21.5" iMac, with an Intel i5 processor, and 4GB RAM (two 2GB sticks), this was the base price model if that helps :)

It says in the user guide that its configurable to 8GB, i guess with the addition of two more 2GB sticks (I think it has space for 4 RAM slots).

My question is, what is the best way for me to upgrade the RAM, do i just buy two 2GB sticks to put me up to 8GB, if so which RAM is the best for me to buy).

Or can i purchase two 4GB sticks to upgrade the RAM to 12GB?

Help would be much appreciated as i really don't want to mess it up.
 
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2 slots, not 4

Your iMac is expandable to 8G. There are two ram slots tho, not 4. Make sure you either put in one 8G ram or 2-4G. The best idea is to keep the ram equal or just use one.

I like Kingston and buy it online (Amazon). Replacing the ram is easy but treat it gently as you should with any other computer parts. Best rule is if it doesn't go in easily, don't jam it.

Hope that helps.
 

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21.5 iMac 3.06 ghz 12gb ram 500g HD iPad 2 16G
Any iMac after late 2009 is expandable up to 16gb and there are in fact four memory card slots on the iMac...from 2009 on...
 
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I agree with Codda, your Mac is in fact expandable to 16GB at least. I say at least because I've heard of folk cranking it up to 32gb. Wouldn't want to try it myself though...
 

Raz0rEdge

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Any iMac after late 2009 is expandable up to 16gb and there are in fact four memory card slots on the iMac...from 2009 on...

I agree with Codda, your Mac is in fact expandable to 16GB at least. I say at least because I've heard of folk cranking it up to 32gb. Wouldn't want to try it myself though...

I thought so too, but Apple's Apple - iMac - Compare the 21.5- and 27-inch iMac. says that the base 21.5" iMac can only be upgraded to 8GB..
 
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Raz0rEdge

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Slydude

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Could this be a case where the chips thar fit that model are a higher density than what was available when the specs were developed when that model was released. The memory information fro Other World Computing shows similar numbers for several other models.
 
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I can personally confirm that the mid-2010 model iMac will take 16 GB of RAM quite readily. There's no reason the current models wouldn't.
 
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Thanks for your replies guys :D

think i'm gonna pick up two 4GB sticks and push it up to 12GB and see how i go :D
 

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I think there's some confusion about the memory capacity of the 2011 21.5" iMacs and that's because there are actually two models:

Mid 2011 21.5" iMac which Apple says can take up to 16 GB but that Mactracker says can actually hold 32 GB.

Late 2011 21.5" iMac (educational model) which Apple and Mactracker both state can only hold 8 GB.
 
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iMac 7,1 and 8,1 RAM and OSX Upgrade

Greetings, this is my iMac OSX and RAM upgrade story (hope it helps);

I wanted to upgrade from OS 10.5.8 (Tiger) to 10.8.2 (Mountain Lion) on my mid 2007 24" iMac 7,1 with Intel Core II Duo 2.4 GHz processor.

Had to first install 10.6.8 (Snow Leopard) which I had to buy over the phone from Apple since they took it down from their website (ridiculous)... $20.00. Got the disc (they paid the shipping, thanks Apple) and the system installed easily, then updated itself over the internet to 10.6.8... perfect, so far so good.

Snow Leopard worked perfectly. However, my iMac only had 1 GB of RAM, and so I had to upgrade that in order to install Mountain Lion, (min 2 GB RAM needed)... So I decided to upgrade to 4 GB.

There are alot of threads regarding iMac RAM upgrades so hopefully this helps clear up some confusion: I bought 2 x 2GB RAM modules from Memory Express.

These were Kingston, 2 GB SODIMM DDR2 667 MHz, PC2-5300, 200-pin modules (memory for notebooks). Product Number: KVR667D2S5/2G (35.00 ea.)

I intalled these and they worked perfectly. Some threads say that they are not compatible but they seem to be working fine, they were recognized, and my computer is blazing fast now... Keep in mind that iMac 7,1 can be upgraded to 6 GB RAM, however my computer nerd friend told me that if you install 2 modules that are different sizes (ie 2 GB and 4 GB) then your dual memory channels cannot be double called by the CPU for maximum speed... 6 GB gives you maximum RAM, but 4 GB (2x2 GB) gives you maximum speed.... something to think about.

My iMac 7,1 is running much faster with its new 2x2 GB RAM upgrade (compared to 1 GB the speed now borders on premonition...)

After this install I was able to download and install Mountain Lion from the App Store ($20.00) and have never looked back. Mountain Lion runs quickly, and even auto-adjusted my screen colour/contrast to make things look nicer upon install... Thanks Apple... The new multiple desktop scheme (spaces) takes some getting used to (10.6.8 was better with the tiled desktops (spaces)). But the new OS runs smoothly. This computer is only used for light work, internet, accounting, etc etc... and for that, Mountain Lion is perfect. No complaints so far.

Time Machine Backup before installing any new operating system though (just in case)... Many threads put Mountain Lion in a very negative light, but so far it has worked perfectly for me, and my iMac is over 5 years old...

Also,

I also have an iMac 8,1 (mid 2008) with Intel Core II Duo processor (2.8 GHz)... This thing is dual booted with Windows XP (SP3, 32-bit) and OSX 10.5.8. I upgraded the RAM on this machine to 4 GB using the following modules;

Kingston 2x2GB, SODIMM DDR2, PC2-6400, 800 MHz, 200-pin modules. Product Number: KVR800D2S6/2G (Memory Express)

These are also compatible and working perfectly. No problems to report so far. Plugged them in and away I went. OSX recognizes them as 2, 2 GB modules but Windows XP system information reports the memory as "2.98 GM of RAM" ... so that could be a problem I guess. However, consulting the Windows forums seems to suggest that this is "NORMAL" and can be fixed if you mess around with your boot files in the root folder of your system drive...... or something The RAM reported by the System Properties dialog box and the System Information tool is less than you expect in Windows Vista or in Windows XP Service Pack 2 or later version

But nonetheless my computer boots both operating systems quickly and can handle a high number of applications at once. This machine is used for data analysis for research purposes (electrochemical lithium ion battery data) and is underpowered for the job (big surprise). However, the RAM upgrade seems to help the Windows XP functionality for crunching large data sets, so the error in reporting the amount of RAM may not be anything to worry about...

Happy upgrading!!
 
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Greetings, all...!

I will be upgrading the memory in my mid-2011 27-inch iMac 2.7GHz i5 which currently has the factory-installed 4GB of memory.

I purchased this 8GB memory stick from Crucial and it's on it's way here.

To tell the truth, I meant to purchase two 4GB sticks, but I chose this single stick instead (I wasn't paying close enough attention, I suppose).

Anyway, to make a long story short, will I be able to plug the new 8GB stick into the machine without any adverse effects? That will mean that the one remaining memory slot will be empty. Is that OK?

If it's not OK, do I have other options than these:

1. Order another 8GB memory stick (to slide into the empty slot). That would make a total of 20GB. I didn't particularly NEED that much memory, but I guess it's not a bad thing....

2. Return this single 8GB stick and order two 4GB sticks. That would make a total of 12GB.

My main question is, will an empty memory slot make the computer act strangely??

Thanks!!

Screen Shot 2012-12-08 at 12.34.20 AM.png
 

chscag

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To answer your questions: Memory works best when installed in identical pairs. The reasons are many and are beyond the scope of what really matters here....

Order another 8 GB module from Crucial and install it along with the first one you ordered. 20 GB of memory may be overkill, but so what? ;)
 
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To answer your questions: Memory works best when installed in identical pairs. The reasons are many and are beyond the scope of what really matters here....

Order another 8 GB module from Crucial and install it along with the first one you ordered. 20 GB of memory may be overkill, but so what? ;)
That's what I thought, but I wanted to be sure. I was reading somewhere that both memory slots in the "top" slots must be filled or the iMac won't even start up. I don't EVEN want to deal with a hassle like that. I just ordered an additional 8GB from Crucial, so my iMac will stay virgin until both 8GB sticks arrive and they'll go in at the same time. 20GB will definitely be overkill for me but it's good to have enough if I ever need it.

Thanks!
 

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