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Can the Late 2009 27" iMac handle 32GB of RAM?
- Thread starter gatortpk
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I would assume so seeing that the 1333MHz RAM I purchased from Amazon Japan is the same spec and I've been using it for years without any issues.
https://forums.macrumors.com/thread...ndle-32gb-of-ram.1327771/page-3#post-17365484
I posted all those details in Apple's forum here:
https://discussions.apple.com/message/22192865#22192865
I wouldn't be surprised if the Late 2009 can run RAM at 1333 MHz. Late 2009 and Mid 2010 27" Core i5/i7 use the same CPU architecture and system bus.
Not to argue but the System Bus Speed of the late 2-09 27"iMac in 1066MHz and that is what it will run at on most of that model, the i7 will run at 1333MHz.
Going way to to your first post I see it is an i7, so yes 1333MHz is the go. Sorry to be confusing.
Going way to to your first post I see it is an i7, so yes 1333MHz is the go. Sorry to be confusing.
You are posting SPECULATION. I am posting BENCHMARKED FACT. It is slightly faster (see my 2 GeekBench scores posted in that Apple Forum thread):
https://discussions.apple.com/message/22192865#22192865
It is an i7 it will run 1333MHz as that is the system bus speed!
It had the wrong mmeory from new!
It had the wrong mmeory from new!
WRONG. Apple only used slower 1066MHz RAM in the late 2009 iMac 27". Why? I have not idea -- ask Apple! But the fact is that 1333MHz RAM will work. I've been using it for years. And it is slightly faster too.
I simply don't understand what you mean. Your previous post says this:
"It had the wrong mmeory from new!"
Since that English is imperfect, I interpreted as meaning, "My iMac had the wrong memory speed installed from the beginning." And because I interpreted your post that way, I wrote my previous post. If that is not what you meant, then I honestly don't know what you mean. Sorry.
Where does it says this?
Everymac page only says 1066 MHz, given it maybe capable, but would be good to get third party confirmation
http://www.everymac.com/systems/app...-i7-2.8-27-inch-aluminum-late-2009-specs.html
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Where is the best place/price to source this 1333MHz RAM to run on an iMac 11,1 - 27" 2.8 i7? -- sorry but your Japanese Amazon link is useless for me, - I don't read Japanese!
The Core i5 and i7 models have the same system bus. In fact, you can upgrade the i5 to an i7 in these iMacs. So if it works in one, it works in both.
Similarly, all the 27" Late 2015 iMacs will run 2133 MHz RAM at its full speed, despite coming preinstalled with 1867 MHz. History repeats itself, as is often the case with Apple.
I have a late 2015 5K iMac at the office and can confirm it has 32MB (Apple branded RAM) running at 1867MHz. Do you have a link to the hardware spec which says it is in fact 2133MHz capable?
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.
Do you have a link to the 2009 iMac i7 has a sys bus of 1333Mhz, and can run said speed RAM?
Download Mactracker and it says the lower end 3.06 GHZ runs 1066MZh and the 3.3GHz and i7 run 1333MHz. From Masctracker late 2009 27" iMac specs.
System Bus 1066 MHz (3.06 GHz Core 2 Duo) or 1333 MHz (3.33 GHz Core 2 Duo) or Intel Direct Media Interface (DMI) at 2.5 GT/s (Core i5 and Core i7)
System Bus 1066 MHz (3.06 GHz Core 2 Duo) or 1333 MHz (3.33 GHz Core 2 Duo) or Intel Direct Media Interface (DMI) at 2.5 GT/s (Core i5 and Core i7)
I am talking about the Core i5 and i7 models, NOT Core 2 Duo. Nowhere did I mention Core 2 Duo.
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Quick web search brought me here: 27" iMac Late 2009 1333Mhz RAM upgrade Success!, so @JDW is not the only one who reported success.
This is awesome, thanks!
I'm running OSX 10.6.8. Do I need to update the EFI, and run the machine in 64 bit mode?
The other thing is I have 2x 2GB RAM modules that came with the machine 1066 MHz RAM -- If I install these with the 2x 8GB RAM -- will it clock all the RAM at the lower 1066 MHz?
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Ok thanks for this. However, I'm running OSX 10.6.8. Do I need to update the EFI, and run the machine in 64 bit mode?
The other thing is I have 2x 2GB RAM modules that came with the machine 1066 MHz RAM -- If I install these with the 2x 8GB RAM -- will it clock all the RAM at the lower 1066 MHz?
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It will run all of the RAM at the lowest speed. So yes, if you leave the original RAM in the machine it will run at 1066 MHz. I have 2x8GB + 2X2GB in mine all running at 1333 MHz.
Ok thanks. So your 2x2GB are 1333 MHz, as usually these iMacs are shipped from Apple as 1066 MHz unless of course you swapped yours out for 1333 speed
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