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32GB RAM in my iMac - IT WORKS!

I purchased four modules from Amazon at £40 each

8GB Module - DDR3 1333MHz
Part Number: KTA-MB1333/8G

I fitted them last night and checked the system and it was ALL OK! :)

TBH, watching the System Memory usage in the Activity Monitor, the _kernel used to consume around 400MB with most of the applications (chrome with several tabs, iTunes, Picasa, Dreamweaver, iMovie) consuming around the 500MB mark and the pretty little pie chart indicator used to mainly be yellow with a dash of red, blue and (if i was lucky) green but now the _kernel consumes around 1GB and the pie chart is mainly green with a dash of yellow. So i am guessing/hoping less swapping will occur and this will speed up some application performance. I did not take any notice of the page ins and page outs but lets see if i notice any great performance difference!

I do know Amazon are selling more of these modules with an increased price of around £47 each. Now to get rid of my four 2GB Hynix modules...
Okay.. but which iMac?
 
I have read that the 2010 and later 27" iMac models can support 32GB of RAM with the new 8GB DDR3 SO-DIMMs.
I read that too, so I thought I'd push it and order two 8GB modules - but it turned out to be a rumour...duh - this is the right website for rumours.

I have an iMac (Mid 2010) with i3 processor. The 8GB modules are not compatible. They fit, they are recognised in "About this Mac" they are the same speed: 1333MHz, DDR3 PC3-10600 SODIMM 2Rx8 1.5v. THEY DON'T WORK.
 
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Hi, I have tried 1600mhz module from Hynix, and it works when installed only in lower right slot
 

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2133mhz Ram Test Results

I can also confirm that it works here with mine. After initially getting kernel panics due to a defective pair which I returned/replaced, it has been running perfectly fine.
View attachment 697406

Hi!

I have upgraded my late 2009 iMac to 32GB. The RAM is shown as OK but I am getting kernel panics continuously. Could you advise me how to find if any of the four modules is defective so I am able to replace it?

Thanks!
 
Thank you . I read all of them in this topic. I have just tried to understand KVR1333D3S9/8G model ram ok or not.

I cannot speak about BRANDS. I can only tell you what I used in terms of SPECS. Your preferred KINSINGTON RAM appears to match the RAM I use according to these specifications:

2pcs of 8GB DDR3-1333 PC3-10600 CL9 204-Pin SODIMM

Because of that, you should be fine. Don't let the 1333MHz speed worry you. I can tell you from years of experience (since 2013) that it works great in the late 2009 iMac 27".
 
I cannot speak about BRANDS. I can only tell you what I used in terms of SPECS. Your preferred KINSINGTON RAM appears to match the RAM I use according to these specifications:

2pcs of 8GB DDR3-1333 PC3-10600 CL9 204-Pin SODIMM

Because of that, you should be fine. Don't let the 1333MHz speed worry you. I can tell you from years of experience (since 2013) that it works great in the late 2009 iMac 27".
Thank you ..
 
I cannot speak about BRANDS. I can only tell you what I used in terms of SPECS. Your preferred KINSINGTON RAM appears to match the RAM I use according to these specifications:

2pcs of 8GB DDR3-1333 PC3-10600 CL9 204-Pin SODIMM

Because of that, you should be fine. Don't let the 1333MHz speed worry you. I can tell you from years of experience (since 2013) that it works great in the late 2009 iMac 27".

I just bought this one and it doesn't boot (long beep every 5 seconds or three beeps)

Crucial 16GB Kit (8GBx2) DDR3/DDR3L 1333 MT/s (PC3-10600) SODIMM 204-Pin Memory For Mac - CT2K8G3S1339M


I tried these as well:
OWC 16GB (2 x 8GB) PC8500 DDR3 Non ECC 1066 MHz 204 pin SO-DIMM Memory Module (OWC8566DDR3S16P), for 2010 MacBook Pro, MacBook, Mac Mini, and 2009 iMac


Timetec Hynix IC 8GB Kit (2x4GB) Apple DDR3 PC3-8500 1066MHz


Maybe there is something wrong with my iMac, this is not normal.
 
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I just bought this one and it doesn't boot (long beep every 5 seconds or three beeps)

Crucial 16GB Kit (8GBx2) DDR3/DDR3L 1333 MT/s (PC3-10600) SODIMM 204-Pin Memory For Mac - CT2K8G3S1339M


I tried these as well:
OWC 16GB (2 x 8GB) PC8500 DDR3 Non ECC 1066 MHz 204 pin SO-DIMM Memory Module (OWC8566DDR3S16P), for 2010 MacBook Pro, MacBook, Mac Mini, and 2009 iMac


Timetec Hynix IC 8GB Kit (2x4GB) Apple DDR3 PC3-8500 1066MHz


Maybe there is something wrong with my iMac, this is not normal.

It's hard to believe I just got lucky. Here's the exact RAM I purchased from Amazon Japan, which is still working in my late 2009 27" iMac i7, by the way:

 
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iMac 11,1 (i5, 27").

Bought a 16GB (2x8GB) Corsair Macmemory CMSA16GX3M2A1333C9 -kit a year ago and a second one few weeks ago. So, now I am running 32GB of 1333MHz memory and absolutely no problems.
 
I just installed these (8Gb x 2) from Amazon:

My iMac 27 Late 2009 i7 started and is working fine, total memory 24Gb rn (Old 4Gb x 2 + new 8Gb x 2). Huge difference!
Thanks for this thread!!
 
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