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What RAM to buy to update new iMac launched today?
- Thread starter spinstorm
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Swap it out before turning it on. RAM doesn't store any data when your iMac is turned off so you'll be fine.
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I believe it does. The iMac uses dual channel memory. Unfortunately, the online guide does not say what slots to use.
don't do that, it runs dual channel so it will actually slow down if you use a single chip. Go with either two more 8GB or two 16GB.
Thanks for your reply. The reason why I am thinking of doing that is to keep the last slot free in case I want to add another 16 GB later.
Keep in mind that dual channel requires the same ram type & brand...& you may find you will never see the price drop because that chip discontinues for a better build. Bite the bullet now, pay for lesser cheaper ram, or wait entirely.
So if I buy 2x16 and add them to the factory 2x4 for a total of 40, you're saying that will prevent dual channel mode? Or it's ok as long as each pair is the same?
(Edited error - previously said 2x8 for the factory RAM)
(Edited error - previously said 2x8 for the factory RAM)
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It will still dual channel. When you get your iMac, look at the chips in it...should only be two. Insert the other two in the two open slots & they will be dual channel. Basically, the memory slots are designed in pairs...that's where you plug them into. As long as the two chips are exactly the same & in the paired slots, they will run dual channel.
I wonder why no one has mentioned Kingston ram at all. The Hyper X ddr4 2400 has a CL rating of 14. Is it compatible with iMac?
I actually did mention considering the Kingston, but I went with OWC because of the CL11 label. Turns out after the fact, they renumbered that to CL17...I may end up swapping it again for something faster.
I'm looking at the Kingston HyperX Impact (HX424S14IB/16) - 16 GB x 2
OR
Crucial (CT16G4SFD824A) - 16 GB x 2
Price is almost the same (Kingston is local, Crucial from Amazon.ca). The Kingston is CL 14, the Crucial is CL 17.
Any thoughts on those?
OR
Crucial (CT16G4SFD824A) - 16 GB x 2
Price is almost the same (Kingston is local, Crucial from Amazon.ca). The Kingston is CL 14, the Crucial is CL 17.
Any thoughts on those?
Go with the Kingston. I'm trying to get the info on the pre-installed memory for the CL rating. OWC sold me CL11 memory, but list it now as CL17, a massive slowdown. I'll probably end up returning it if it isn't 11 & go for the kingston myself.
I don't know about the 2666MHz but I've ordered 2x16GB of the 2400MHz Ballistix for the iMac that I've also just ordered and I shall report as soon as they've both arrived.
Drop in nanoseconds of delay...probably only noticeable in benchmarks & things that require the memory to constantly go back and forth. IOW, 95% of us wouldn't notice a difference. That being said, I still don't know what apple installed.
So i am thinking i am going to buy The ballistix one. Ballistix Sport LT 32GB Kit (16GBx2) DDR4 2400 MT/s (PC4-19200) SODIMM 260-Pin - BLS2K16G4S240FSD (Gray) https://www.amazon.com/dp/B01DGOF3E4/ref=cm_sw_r_cp_api_c2Oozb8VVJXRB
Or Also i was thinking The crucial one
Crucial 32GB Kit (16GBx2) DDR4 2400 MT/s (PC4-19200) DR x8 Unbuffered SODIMM 260-Pin Memory - CT2K16G4SFD824A https://www.amazon.com/dp/B019FRCV9G/ref=cm_sw_r_cp_api_A5Oozb3NGW3M7
Can i put this 2 cards in combination with The 8gb that The imac comes with for a total of 40gb ram? 16+16+4+4=40
Or Also i was thinking The crucial one
Crucial 32GB Kit (16GBx2) DDR4 2400 MT/s (PC4-19200) DR x8 Unbuffered SODIMM 260-Pin Memory - CT2K16G4SFD824A https://www.amazon.com/dp/B019FRCV9G/ref=cm_sw_r_cp_api_A5Oozb3NGW3M7
Can i put this 2 cards in combination with The 8gb that The imac comes with for a total of 40gb ram? 16+16+4+4=40
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I would avoid the Crucial because I'm nearly certain the Apple RAM is going to be 16 chips (8 on each side) for 8GB and larger DIMMs. I had major problems on my Late 2013 iMac with similar Crucial RAM back in the day. If you are going to go with Crucial I'd recommend ordering from them directly (like this part - 8 chips per side) or getting the model number of their 2017 5k-certified RAM from their website and trying to find that on Amazon or elsewhere.
Also, to possibly answer a question posted earlier in this thread, Crucial's 2017 5k iMac RAM is certified to Apple's specifications so it looks like the stock RAM is CL17.
That's my plan. I'll let you know about that config with the Ballistix Sport. The RAM arrives tomorrow but my iMac won't be here till later next week.
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Witch one did you buy of the Ballistix the 32gb i mean 2 cards of 16gb each or did you go with 4 8gb cards?
[doublepost=1497014613][/doublepost]How about this one?
whats the diference between this one and the Ballistix one?
https://www.amazon.com/Kingston-Tec...ywords=Kingston+HyperX+Impact+(HX424S14IB/16)
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I was just looking at the 21.5" iMac 2017 teardown by iFixit and searched the specs of the RAM module that is included in the 21.5" iMac, as seen in this photo from iFixit.
According to Hynix this module is CL-17.
https://www.skhynix.com/products.view.do?vseq=1893&cseq=75
I figure that the 27" uses the same type of RAM modules with CL-17.
That's not to say that faster RAM like the CL-16 Ballistix won't work fine or even faster... I guess we'll have to wait for feedback from our fellow forum members that have bought Ballistix sticks!
According to Hynix this module is CL-17.
https://www.skhynix.com/products.view.do?vseq=1893&cseq=75
I figure that the 27" uses the same type of RAM modules with CL-17.
That's not to say that faster RAM like the CL-16 Ballistix won't work fine or even faster... I guess we'll have to wait for feedback from our fellow forum members that have bought Ballistix sticks!