Will I lose dual channel by putting factory sticks in 1&2 and new sticks in 3&4. I know the speed stays the same but will I lose dual channel and is dual channel worth it on a 2020 iMac with i7??
8x8x16x16
Put the 16GB sticks in 1&2 and the 8GB sticks in 3&4.
If the iMac has problems with all four sticks installed, then return the 16GB Corsair RAM and buy compatible RAM sticks from either OWC or Crucial.
That should give you dual channeling with matching modules in Channel A and Channel B.
What 2 16GB modules are you adding to the 2020 iMac?
Mac's are very picky. The spec's and supplier are the most important thing to worry about.
Your best bet, is to follow the instructions at > Install memory in an iMac - Apple Support
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.
Ah yes, I cannot answer that come to think of it, but these people are tops in service & knowledge...
Customer Service (macsales.com)
You can count on their answer 100%, they even make there own RAM for Macs.
Then why does Apple put matching sticks in 2&4 from the factory?
And then Apple says this...minimize the capacity difference between Channel A (slots 1 and 2) and Channel B (slots 3 and 4) when possible.
2 factory sticks 8GB each.
I purchased CORSAIR - Vengeance Series 32GB (2x16GB) 2666MHz DDR4
For now I have taken out the factory stick and have the Corsair in their place 2 & 4 slots.
Thank you. However that post is from 2014. Surely the way Mac OS uses RAM has changed since then, not to mention Intel. Also, I have found that rkaufmann87 has contradicted themself when talking about dual channel RAM on Mac. According to that user I should do the RAM 8x8x16x16. Which also isn't what Apple says. SO on a 2020 iMac do you lose dual channel with that config? Thanks!
But what about dual channel?
Not sure I'm on the same page as you. Having same sticks in 1&2 and 3&4 would remove dual channel?
1 & 2 are a set, 3 & 4 are a set, 1 & 3 or 2 & 4 are not tied together.0
I should've waited for someone else to answer, now I'm not sure of anything, or which way the pairs of slots are tied together... sorry. :O
2020 iMac RAM upgrade.
