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ivanjay205

macrumors newbie
Original poster
Jun 9, 2014
23
2
Hi everyone, I recently bought my first mac and am loving it. I got the 2019 model with 8 gigs of ram and I bought some aftermarket ram from OWC. I read a lot about dual channel vs single channel. I left the Apple default RAM in the 1st and 3rd slot and installed my 16 gig each (additional 32) in 2 and 4. It looks like it is fine but it did seem to boot a bit slower. This is what I see in system information so I am thinking I am not in dual channel mode? Is this an incorrect install and how do I properly pair them? I would think the sizes should be in matching channels.
 

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Hi everyone, I recently bought my first mac and am loving it. I got the 2019 model with 8 gigs of ram and I bought some aftermarket ram from OWC. I read a lot about dual channel vs single channel. I left the Apple default RAM in the 1st and 3rd slot and installed my 16 gig each (additional 32) in 2 and 4. It looks like it is fine but it did seem to boot a bit slower. This is what I see in system information so I am thinking I am not in dual channel mode? Is this an incorrect install and how do I properly pair them? I would think the sizes should be in matching channels.
For the 2019 iMac, the way you have arranged the RAM is correct.
You have dual channel because the size of sticks in Channel A match the size of sticks in Channel B.
And all are running at full speed (2667 MHz).
AFAIK, there is no utility that reliably states "you are running in dual channel." There are some utilities that incorrectly state the RAM is in dual channel.
I suggest run Novabench RAM speed test, and you should get about 28,000 MB/s RAM speed (I think), if nothing else is running.

btw, this arrangement would not work well for the 2020 iMac (the speed would drop to 2133 MHz, which is a quirk of only the 2020 iMac).
 
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For the 2019 iMac, the way you have arranged the RAM is correct.
You have dual channel because the size of sticks in Channel A match the size of sticks in Channel B.
And all are running at full speed (2667 MHz).
AFAIK, there is no utility that reliably states "you are running in dual channel." There are some utilities that incorrectly state the RAM is in dual channel.
I suggest run Novabench RAM speed test, and you should get about 28,000 MB/s RAM speed (I think), if nothing else is running.

btw, this arrangement would not work well for the 2020 iMac (the speed would drop to 2133 MHz, which is a quirk of only the 2020 iMac).
Thanks! Is there any benefit to having the larger ram first or it doesn’t matter
 
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