Can anyone answer the question above about faster speeds working on this iMac?
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What RAM to buy to update new iMac launched today?
- Thread starter spinstorm
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This is an excellent idea.
If anyone is taking out the stock RAM and is looking to sell, please PM me.
I thought this was a great idea too, until I saw the prices that people are selling their RAM for on ebay here in Germany. 80-90 Euros for 8 GB of used RAM is a little steep. Especially when I can get new Crucial RAM for 65 Euros. So I'm back to my original questions. 1x8 vs 2x4, does it make a difference? And should it be dual or single rank RAM?
I ordered the non iMac specific crucial ram (16gb x 2) from BH that others have mentioned on this thread. Plugged it in and it's working fine. Ran memtest and no issues.
Crucial part no is CT2K16G4SFD824A. Much cheaper than OWC ($240 vs $320). The iMac specific ram is CT2K16G4S24AM and is out of stock everywhere.
Crucial part no is CT2K16G4SFD824A. Much cheaper than OWC ($240 vs $320). The iMac specific ram is CT2K16G4S24AM and is out of stock everywhere.
For those installing new RAM, are you following the instructions and laying your iMac flat on a table, or just doing it whilst it's standing up?
That's ridiculous! I'm sure you can find someone who will to sell it to you for a more reasonable price here. I just sold mine for €40.
Damn, you were spot on, it forced all my modules down to 2133mhz. Guess an RMA is on the cards :-(
Thank you very much! I hadn't spotted that. Ok that settles it, RMA it is. I really appreciate you pointing that post out to me.
There are now even higher scores at that link. The highest (>10% above Onionbobo's) lists 32GB 3000 MHz RAM. Other RAM speeds for those higher scores include 3600, 3333, 3111, 3020, 2747, and 0 (?!?), with total RAM ranging from 16GB to 32GB. One even used only a iMac18,1 (i7-6700K @ 4.01 GHz) but with 3333 MHz RAM. How accurate are those listed speeds (aside from the 0), and are the highest speeds safe to use? I'm looking for the fastest stable RAM.
most likely not, but a kit is guaranteed to be 100% identical paired ram. buying twice the same part number might not be exactly the same thing if they came from different batches or revisions.
Thanks, unfortunately before asking the question above, I already ordered two 16GB Crucial (CT16G4SFD824A) sticks (using a 1-click order with Quantity 2, with the items sold directly by Amazon, not a 3rd party), because the price for the 2x kit was a little higher. Is there a simple way for me to check or test the RAM upon receipt to confirm whether they are mismatched in any relevant way (and then return them if necessary), or could they be mismatched in a way that causes subtle problems now or later that aren't readily detectable now? I might still be able to cancel the order but then I'd have to wait longer for a replacement.
BTW, since I was very unclear about the best choice of fastest RAM (e.g., the HyperX 2400MHz CL14, or some other >=3000 MHz option) and I wanted more RAM ASAP, I ordered the above Crucial part (despite it not being the official Mac part, I understood it to be a very safe choice and possibly identical to that part). But I'd still prefer to get faster RAM ASAP if it's stable, and remain willing to switch now or later. If I knew the best alternative, I might not mind trying to cancel the Crucial order right away.
I highly doubt you are going to have any problems by ordering two pieces of the same brand/model/part number, even if they aren't from the same batch.
I ordered two separate packages of Crucial Ballistix Sport 16GB because it was a lot cheaper than the 2x16GB packs. I ultra-stress tested it with Memtest86 at extreme temps here for about 6 hours and in addition to over two weeks of heavy usage haven't seen a hint of any problems whatsoever.
Best can only be defined by you. For me, best was keeping the stock RAM for a total of 40GB. I am not concerned with getting an extra 5-10% of speed by lower CL parts or overclocking. I just wanted a good, stable 40GB for now (64GB down the road) and I've gotten it.
Thanks, I also assume that even the highly unlikely potential problems specifically caused by not buying a kit (as opposed to other potential problems that always exist even with a kit) would only be slightly degraded performance (but not actual errors or failure) from a slightly mismatched pair, since each stick is supposed to function without being part of a pair or dual channel.
Was there a reason you preferred the Crucial Ballistix Sport over the "normal" Crucial 2400MHz CL17 that I just ordered, if you’re using them with the stock 8GB (which I thought was 2400 CL17)? I recall seeing Ballistix Sports at 2400 and 2666 MHz, both CL16, which I assumed would both drop to 2400 CL17 when used with the stock RAM. Was one of your goals to benefit from the lower latency and/or increased speed later when you replace the stock 8GB with another matching 32GB?
Yes, I of course wanted to decide what would be best for me, but I can’t yet because I'm still trying to identify the potential choices that will even work with this iMac (aside from the HyperX 2400MHz CL14, I've seen little to no information yet about other faster RAM working with this iMac). (Edit: I've also seen conflicting feedback about whether the HyperX 2400MHz CL14 would work properly with this iMac.)
I’d definitely want even 5-10% more RAM performance if that were available by replacing the stock 8GB with 32GB (or 64GB) of Kingston 2400MHz CL14 or Ballistix 2666MHz or G.SKILL 3000MHz (provided there would be no increase or a sufficiently small increase in risk, which is why I also mentioned safety). I don’t even know yet whether there would be any meaningful safety tradeoff with faster RAM. If there is only really a cost tradeoff (as I assume is true for the CPU choices), I’d almost certainly choose the fastest RAM (as I did with the iMac CPU).
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It was my main goal just to get an additional 32GB of compatible RAM and at the time it was not just the cheapest option for me but the only one here in Japan. I ordered it about one month ago right after I ordered the iMac. Since then the other Crucial parts, including "For iMac" have become available. This the 2400MHz model, but it is CL16 and I am aware that it is likely clocking back to CL17 to accomodate the Apple stock RAM for now. I will eventually add another 2x16GB of Ballistix and I should get that small performance boost.
Based on this it sounds like you might want to cancel the Crucial order and go for the Kingston Hyper-X. The reports from users in this thread who dumped the stock RAM in order to use it alone seem to be positive and the posted benchmarks do show improved performance. I haven't seen too many report of other high-spec'ed RAM in the 2017 iMac. You might want to check out Apple's discussion forums as well.
Checking out Apple's forums makes sense. Although it's too late to cancel the Crucial order, I can return it and I remain interested in a faster reliable alternative. I almost ordered the HyperX, but didn't for various reasons, such as: (1) Claims by multiple customers on Amazon that it didn't work on this iMac even alone (although it worked for some other customers); (2) another product might be materially faster than the HyperX, as suggested by Geekbench; (3) my uncertainty about increased instability from using faster RAM of any kind (I remain unclear whether this should be a concern for higher clock speed or lower CL or both or neither); (4) feeling that Crucial may be a more reliable brand. I wonder whether any substantial long-term differences in reliability based upon brand or speed can be eliminated by extensive short-term testing (such as you've described) within the return period.
I just got my i7 with 8 gigs.
Bought the same ram as SaSaSushi (thank you!)
only thing.
2 4 gig sticks were not next to each other.
I had to move the default ones next to one another. slot 1 and slot 2.
added the new ram to 3 and 4.
(would NOT work unless I did that.)
now I have 40 gigs of ram.
all is awesome!
Bought the same ram as SaSaSushi (thank you!)
only thing.
2 4 gig sticks were not next to each other.
I had to move the default ones next to one another. slot 1 and slot 2.
added the new ram to 3 and 4.
(would NOT work unless I did that.)
now I have 40 gigs of ram.
all is awesome!
My information is still very incomplete, but I mentioned above some other potential options I've seen with higher clock speeds, such as the G.SKILL 3000MHz and the Crucial Ballistix Sport 2666MHz CL16 (which also has higher latency than the HyperX so it may be slower for many applications). Geekbench shows tests with even higher speeds above 3000MHz, but I haven't yet seen any such products. The highest Geekbench score used 3000MHz RAM, so I'd like to know what product that was.
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I thought matching sticks were specifically supposed to be in slots 1 and 3 (and then 2 and 4).
