order of RAM chip placement...

My next iMac purchase will probably be an Apple-refurbished 27" iMac. It has 4 user-serviceable, 2666mhZ so-dimm slots and will accept up to 4 - 32GB 2666mhZ, SO-DIMM 260 pin chips (total: 128GB RAM).

My question: if the size of the chips are different (2 - 4GB plus 2 - 32GB), does it matter which slot I place them in?

iMac Line (2012 and Later)

Posted on Dec 25, 2021 5:05 AM

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3 replies

Alan Blair Author

Level 1

15 points

Dec 25, 2021 9:26 AM in response to Ronasara

These 4 slots are lined up one in front of the other. According to Apple, any one slot is as good as the next. They do recommend the GB size for all 4 be close to each other: 4GB chip with a 16 or a 32GB chip not recommended.

dialabrain

Level 10

137,429 points

Dec 25, 2021 5:18 AM in response to Alan Blair

Install memory in an iMac - Apple Support

Ronasara

Level 6

15,553 points

Dec 25, 2021 9:15 AM in response to Alan Blair

As I understand it, the memory in the two side-by-side slots should be identical. But they can be more or less memory capacity than the other two slots

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order of RAM chip placement...