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Maximum RAM limit
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Hardware. You can find specs on all Apple products, including maximum RAM:
- By visiting EveryMac.com: Actual Maximum RAM
- By selecting your model on the Crucial Memory Advisor Tool to find RAM information
- By using Mactracker
- By entering your serial number here to find specs for your model.
(Be aware that some models can use more RAM than Apple shows. Check EveryMac to verify actual usable RAM.)
It is limited by the hardware. Each Mac has a bay of RAM chips, a basic 4GB model will have two 2GB chips. A modern iMac will have four available slots (two already filled). You can buy RAM in sizes up to 16GB, I believe, meaning that 4 slots can have 64GB of RAM, which would mean replacing your original 4GB. You can also add RAM chips to the two empty slots for up to 36GB.
**Sorry, this is completely wrong!
It IS limited by hardware but the numbers are wrong. An iMac can have up to 32GB.
**Sorry, this is completely wrong!
It IS limited by hardware but the numbers are wrong. An iMac can have up to 32GB.
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The iMac doesn't support ram over 16GB, its not read or usable. The hardware limits it. Not all motherboards/logic boards can support huge amounts of ram like that.
That's not true. Many iMac models support up to 32GB. Read the links posted to get the facts.
The 2011 iMac can support up to 32 GB RAM with four 8 GB of 204-pin DDR3 SO-DIMM RAM modules, the current maximum in that size.
Since the OP did not specify, what exact iMac s/he is talking about, and the signature mentions a 2006 iMac, we can't really help.
Mister GGJstudios though gave the OP the means to let the OP help him or herself.
His 2006 iMac in his sig does not though..
Edit: The 2006 iMac supports up to 4GB of ram, I thought they supported 16GB then hmm. Which iMac only support 16GB was it 2010 ?
No, but since the OP didn't specify which iMac they were inquiring about, the links will enable them to find the facts for whichever model they want.
Some of the 2010 models support a max of 16GB, some 32GB. The EveryMac.com links will show which.
Yes but theres many different models some showing 32 some showing 16 so I wasn't sure if the information was right. Seems that just a variety of the 2010 models had different maximum ram.
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Yeah thanks I found that while looking, wasn't sure if it was a mistake or not didn't think they would have different max amounts on the same year model.
In 2010, only the 27" supported 32GB, while the 21.5" maxed at 16. The next year, they both supported 32.
ah, well I recently bought a 21.5 iMac from the higher ed store, (2011 model) they told me that the iMac only would read 16GB of ram (when I asked them about voiding warranty etc on replacing ram and the hdd)
So I wonder if they got mixed up and were thinking about the 2010 model.
Quite possible, but more likely is the fact that Apple has routinely claimed a lower max RAM than models are capable of using.
Not Just H/W ... Software Too
Other World Computing sells after market Memory upgrades for MacPro. Apple says max 64GB, but OWC sells a 128GB upgrade kit. There is one caveat though, you must boot into Windows via Bootcamp because Mac OS X will only recognize 96GB of RAM. I've been trying to find more info on why that limit exists if OSX is a 64-bit OS.
Other World Computing sells after market Memory upgrades for MacPro. Apple says max 64GB, but OWC sells a 128GB upgrade kit. There is one caveat though, you must boot into Windows via Bootcamp because Mac OS X will only recognize 96GB of RAM. I've been trying to find more info on why that limit exists if OSX is a 64-bit OS.
Thanks for all the good, honest answers. I wasn't really asking what my iMac could use, just whether the limit was software or hardware based, which has been answered very well.
Thank-you.
Thank-you.
You're correct. I wonder if High Sierra (10.13) or Mojave (10.14) has increased this software limitation?
On older Macs the limit was imposed by what memory modules were manufactured at that time,
For example, the 2011 27" iMc as quoted above on release took a maximum of 4 x 4GB modules, total 16GB. After release of 8GB modules, which worked in that model, this then became 32GB.
For example, the 2011 27" iMc as quoted above on release took a maximum of 4 x 4GB modules, total 16GB. After release of 8GB modules, which worked in that model, this then became 32GB.
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