Skip to main content
Help

Current version by: Dan ,

Text:

-If we review this Apple T/N [https://support.apple.com/en-us/HT201191|Install memory in an iMac]
+If we review this Apple T/N [link|https://support.apple.com/en-us/HT201191|Install memory in an iMac]
We’ll find this statement “If you have mixed capacity DIMMs, see the install memory section for installation recommendations.” And we jump down to that section: “iMac (Retina 5K, 27-inch, 2020) DIMMs have a notch on the bottom, slightly left of the middle. '''''If your DIMMs are mixed in capacity, minimize the capacity difference between Channel A (slots 1 and 2) and Channel B (slots 3 and 4) when possible.'''''”
So you really can’t mix within the channel only across channels. So you’ll need to install your different RAM sizes in Slot 1 and Slot 3. Don’t forget to allow the system to initialize which can take awhile!
+
+Given the cost and the performance benefit I would just go with a matched pair within each channel pair.

Status:

open

Original post by: Dan ,

Text:

If we review this Apple T/N [https://support.apple.com/en-us/HT201191|Install memory in an iMac]

We’ll find this statement “If you have mixed capacity DIMMs, see the install memory section for installation recommendations.” And we jump down to that section: “iMac (Retina 5K, 27-inch, 2020) DIMMs have a notch on the bottom, slightly left of the middle. '''''If your DIMMs are mixed in capacity, minimize the capacity difference between Channel A (slots 1 and 2) and Channel B (slots 3 and 4) when possible.'''''”

So you really can’t mix within the channel only across channels. So you’ll need to install your different RAM sizes in Slot 1 and Slot 3. Don’t forget to allow the system to initialize which can take awhile!

Status:

open