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Decision time i7 vs i9 for new 2020 iMac?

c0smonaut

macrumors newbie
Oct 4, 2020
1
0
Russia
get the i7 and a bigger SSD
RAM and eventually CPU can be upgraded.
nanoglass is the most retarded excuse to not re-arrange your desk or seating position relative to source of light (a.k.a windows)
Is it true that CPU can be upgraded? And how difficult it is?
 

TheJuice89

macrumors newbie
Sep 27, 2020
13
3
If there are no thermal constraints the i9 10900K will outperform the i7 10700K in single core too because of the higher boost clocks. 5.3GHz vs 5.2GHz, but inside the iMac, the boost clocks for both are capped at 5.0GHz. With the thermal system and constraints the i7 10700K will likely beat the i9 10910 in single-core.

You see this play out with the 10600K which has a base clock of 4.1GHz over the i7 or i9 in more constrained systems where the boost clocks cannot be sustained.
No thermal constraints when running 1 core 100%. According to datasheets at ark.intel.com the max. clock speed for the i7 is 5.1 GHz en 5.0 for the i9. Apple hasn’t capped the clock speed; they do use tailored versions of the CPUs.

Sorry this is a bit above my head. Is the consensus really that the i7 will outperform the i9 in single core performance? Notably? Because the i9 gets hotter in longer sessions? I just want the best processor, single core and multi core seem to be equally important for me. When the i7 would really be the better choice (disregard of the price difference) that would be pretty crazy...

I'm also going for the 5700 or 5700XT, and I don't really care about a little fan noise but I don't want to have an extremely loud radiator in my face (I already have that now) with performance drops because of the heat during long sessions. The i9/5700XT combo is slowly starting to scare me lol but according to Max Tech it shouldn't be too bad.
 

ZBoater

macrumors G3
Jul 2, 2007
8,395
1,091
Sunny Florida
The i9/5700XT combo is slowly starting to scare me lol but according to Max Tech it shouldn't be too bad.

That is the fastest combo on the 2020 iMac. Period.

All this noise and 300 posts to say that it is not worth the extra $400 is very entertaining. But at the end of the day, the fastest 2020 iMac is the i9/5700XT combo.
 
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Mac-key

macrumors 6502a
Apr 1, 2010
669
83
Alabama
I'd say - save your money. I'm a professional photographer and videographer. I edit RAW images in LR and PS as well as do 1080 and 4K video editing in Premiere. I'm on a 2013 iMac i5 I bought used for $650 on eBay last year. I've got a 512 SSD and believe it or not only 8GB of RAM. It handles everything I throw at it. I can edit 4K footage no problem... LR could be a bit faster, but it works and I SAVED a ton buying it.
 

wilberforce

macrumors 6502
Aug 15, 2020
295
236
I'd say - save your money. I'm a professional photographer and videographer. I edit RAW images in LR and PS as well as do 1080 and 4K video editing in Premiere. I'm on a 2013 iMac i5 I bought used for $650 on eBay last year. I've got a 512 SSD and believe it or not only 8GB of RAM. It handles everything I throw at it. I can edit 4K footage no problem... LR could be a bit faster, but it works and I SAVED a ton buying it.
I agree you absolutely do not need a top spec machine for LR and PS. I went from a 2014 5k iMac to a 2020 5k iMac (both i7), and see only slight improvement in responsiveness for photo-editing (aside from batch exporting or importing) - on both machines the responsiveness is virtually immediate to any adjustment, with little to no perceptible lag.

But the 5k screen is fantastic, and really is worth the upgrade from a non-retina screen (IMO).

I also have a low-spec 2015 13" retina MBP. LR and PS are pretty sluggish on that. So it is not as if anything is OK for LR and PS, but any of the 2020 iMacs, including the bottom base model, would be fine, and all have the same great screen.
 
Last edited:

8thNote

macrumors newbie
Jun 7, 2005
17
5
Cincinnati, OH
8thNote - would you mind expanding on this a little please? How much better was 4 x 16 compared to 2 x 32 and how did you test them/tell the difference?

About to order 64GB and wondering which to get. I'd get 2 x 32GB if no real difference as that would allow possibility for upgrade later but if 4 x 16 is noticeably better I might do that - also wondering if 4 x 16GB might run a little cooler.

thanks

There is virtually no difference between 4x16 or 2x32, really.

I put the chips in different configurations and then tested with Geekbench 4 and 5. I liked Geekbench 4 better for testing RAM performance because it would measure RAM bandwidth.

You're welcome to look at my test results: https://browser.geekbench.com/user/338794

Look at the note on each recent test to see my top-to-bottom RAM chip configuration (like 0 32 0 32).
 

sean+mac

macrumors newbie
Aug 13, 2020
14
16
Canada
I haven't been watching Geekbench the past few weeks to see if (finally) aggregate 2020 iMac stats had made it into the standard Benchmark Browser list, scored against other Macs. It looks like there are enough benchmarks now that https://browser.geekbench.com/mac-benchmarks does rank the 2020 models onto the list.

Fastest two 2020 models are 8th and 11th from the top on the "Multi-Core" list (see screenshot.) Those same two models are the top two scores on the "Single Core" list.

1602718596812.png
 

AZREOSpecialist

Suspended
Mar 15, 2009
2,354
1,277
I'd say - save your money. I'm a professional photographer and videographer. I edit RAW images in LR and PS as well as do 1080 and 4K video editing in Premiere. I'm on a 2013 iMac i5 I bought used for $650 on eBay last year. I've got a 512 SSD and believe it or not only 8GB of RAM. It handles everything I throw at it. I can edit 4K footage no problem... LR could be a bit faster, but it works and I SAVED a ton buying it.
Sorry, but I call BS on this lol
 

hoodafoo

macrumors member
Oct 11, 2020
67
18
Lso Angeles
That is the fastest combo on the 2020 iMac. Period.

All this noise and 300 posts to say that it is not worth the extra $400 is very entertaining. But at the end of the day, the fastest 2020 iMac is the i9/5700XT combo.

Not really... here's are my findings (originally posted on another thread):

I gathered 4 pages worth of benchmarks from Geekbench for each of the following: 8-core w/either 5700 (8GB VRAM) or 5700XT (16GB VRAM), 10-core w/either 5700 (8GB VRAM) or 5700XT (16GB VRAM)

Deleted the highest and lowest score and averaged them out:

iMacs with =<64GB system RAM
8C/8GB (9 samples): 46023
8C/16GB (26 samples): 54232*
10C/8GB (2 samples): 43639
10C/16GB (15 samples): 55113

iMacs with >64GB system RAM
8C/8GB (2 samples): 44741
8C/16GB (37 samples): 54776
10C/8GB (3 samples): 46079
10C/16GB (67 samples): 54753

From the numbers, you can see that going from 8GB VRAM to 16GB makes a big difference. Going from 8-core to 10-core has minimal impact and even in some cases a lower score. And seems like going beyond 64GB of RAM provides no benefits at all. So in the end, I went for the sweet spot: 8-core i7/5700XT/64GB*

Errors to take into account: ppl submitting multiple benchmarks skewing the data, RAM installed non-optimally, non-controlled environment
 

naerct

macrumors regular
Mar 19, 2019
153
28
Southern NH
I just installed two top line I-7 27" iMacs for senior photographers. I didn't even consider the matte screen, and decided that the i7 was a better choice for the price. Neither of these photographers shoot video professionally, so I believe the i7 would be sufficient along with the high end video card and 72GB RAM (adding 2, 32GB OWC RAM to the stock 8). Not 72MB. I haven't heard any complaints yet, they really scream. However, I think there are very good reasons to go for the i9, as it has proven itself as the workhorse of the Intel spread. If I was doing any 4K or uncompressed video editing, I think it would be worth the extra $. My only complaint about the iMacs are the screens, especially for printing. After using internally calibrated high bit processing screens (Eizo and NEC) for the last decade, I can never see gray on a Mac screen... I could definitely see using an Eizo in combination with an iMac 27" but not while my 12-core cMP is alive and well in Catalina, thanks to MacRumors fora.
 

ondioline

macrumors member
May 5, 2020
51
45
Is it true that CPU can be upgraded? And how difficult it is?

The CPU is socketed so it can be replaced for sure, I don't think you can actually buy an 'i9-10910' though. I guess you could try putting an i9-10900k into a 2020 iMac but I sincerely doubt the cooler is adequate.
 

hoodafoo

macrumors member
Oct 11, 2020
67
18
Lso Angeles
Everyone seems to think these are the last Intel iMacs, but I'm not so sure. While I won't be surprised if the next top performing iMacs are using Apple's chips, I think transitioning the entire Mac lineup to ARM could be a slow multi-year process. Just because Apple announced ARM Macs are coming doesn't mean their relationship with Intel is completely over.

As for this year's i7 vs. i9, choosing the 8-core doesn't seem to be compromising much in the way of performance, so I put the money into a GPU upgrade instead.

I agree that these won't be the LAST Intel iMacs. I also suspect refreshed iMac Pro's coming before full AS transition. It doesn't make sense for apple to re-engineer the thermal solution in the iMac Pro just for one iteration of release.
 

MikkelAD

macrumors regular
Feb 17, 2018
184
24
72GB RAM (adding 2, 32GB OWC RAM to the stock 8)

I don't know if you have seen it or not, but that configuration isn't optimal for performance. That way these machines probably will keep the speed of 2667MHz but dual channel will be lost. You need to remove the stock 2*4GB and put the 2*64GB in slot 1-3 or 2-4.

You can download 'Novabench' and check for difference in RAM performance to make sure and compare with others in some of the "dedicated" threads about exactly this problem 👍
 

TheJuice89

macrumors newbie
Sep 27, 2020
13
3
Not really... here's are my findings (originally posted on another thread):

I gathered 4 pages worth of benchmarks from Geekbench for each of the following: 8-core w/either 5700 (8GB VRAM) or 5700XT (16GB VRAM), 10-core w/either 5700 (8GB VRAM) or 5700XT (16GB VRAM)

Deleted the highest and lowest score and averaged them out:

iMacs with =<64GB system RAM
8C/8GB (9 samples): 46023
8C/16GB (26 samples): 54232*
10C/8GB (2 samples): 43639
10C/16GB (15 samples): 55113

iMacs with >64GB system RAM
8C/8GB (2 samples): 44741
8C/16GB (37 samples): 54776
10C/8GB (3 samples): 46079
10C/16GB (67 samples): 54753

From the numbers, you can see that going from 8GB VRAM to 16GB makes a big difference. Going from 8-core to 10-core has minimal impact and even in some cases a lower score. And seems like going beyond 64GB of RAM provides no benefits at all. So in the end, I went for the sweet spot: 8-core i7/5700XT/64GB*

Errors to take into account: ppl submitting multiple benchmarks skewing the data, RAM installed non-optimally, non-controlled environment

Thanks, this is interesting nice job!! Is there a reason you used Geekbench 4? Geekbench 4 is more dependent on RAM and GPU than Geekbench 5, right?

I am mainly interested in the CPU difference since that will be my bottleneck, it seems that in your results the GPU (although I doubt if it's the VRAM, I guess it's the better chip of the 5700XT but I'm no specialist at all) makes the difference like you said, not the CPU. Would that be different in Geekbench 5? There is a relatively substantial difference between the i7 and i9 in the Mac charts there.

Also, in your results, you use two categories. =<64 GB of RAM and > of RAM. Wouldn't it be better two just choose the two configurations people use the most, like 32GB and 64GB? In your =<64 GB category there are probably people who run their benchmarks with 8GB of RAM before upgrading with aftermarket RAM, and that will definitely be a bottleneck right? And I guess nobody with an i7 or i9 is going to stick to 8GB of RAM.

I was really going for the i9 but after weeks of reading about it I may be losing my religion. I would love somebody from Apple explaining why they messed up that beautiful 10th gen i9 opportunity..
 
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TheJuice89

macrumors newbie
Sep 27, 2020
13
3
I just went through a few pages of Geekbench 5 and with ideal (32 or 64GB) RAM setups, the i7 hovers around 9000 and the i9 around 10.000.

Non-ideal or too low RAM configuration is a Geekbench killer, penalties around 25%...
 

mmcmonster

macrumors newbie
Sep 20, 2010
4
0
A different approach. (I know little to nothing about the i7 vs. i9)

* This is a work computer. Getting the most power you can is worth it, even if it just saves you a minute a day over the next five years.
* Multi-threading is only going to get more pervasive over the time period you will own the device.
* The multi-threading is not just going to be for your app. It's going to be for all system processes. The benefit in faster multi-threading will mean better system performance while your processor-intensive application is running at 100%.
* It is quite possible that in the time period for your next computer that Apple will either transition away from Intel completely or (less likely) into a hybrid design with an Intel processor combined with an Apple processor. If you want to delay that transition for yourself as long as possible, you get the most powerful (and future-proof) computer you can afford.
 

SalisburySam

macrumors regular
May 19, 2019
158
114
Salisbury, North Carolina
Interesting thread indeed. The OP @BasilFawlty last replied on message #36 way back on August 20. Since his purchase schedule was mid-September, I wonder what he chose, and why. Moving from a 2011 machine to a 2020 one would in and of itself provide huge performance improvements almost regardless of configuration. If the OP intends to get his next update in 2029, I wonder if he felt the i7 or the i9 would get him there.
 

warp9

macrumors 6502
Jun 8, 2017
296
385
I just installed two top line I-7 27" iMacs for senior photographers. I didn't even consider the matte screen, and decided that the i7 was a better choice for the price. Neither of these photographers shoot video professionally, so I believe the i7 would be sufficient along with the high end video card and 72GB RAM (adding 2, 32GB OWC RAM to the stock 8). Not 72MB. I haven't heard any complaints yet, they really scream. However, I think there are very good reasons to go for the i9, as it has proven itself as the workhorse of the Intel spread. If I was doing any 4K or uncompressed video editing, I think it would be worth the extra $. My only complaint about the iMacs are the screens, especially for printing. After using internally calibrated high bit processing screens (Eizo and NEC) for the last decade, I can never see gray on a Mac screen... I could definitely see using an Eizo in combination with an iMac 27" but not while my 12-core cMP is alive and well in Catalina, thanks to MacRumors fora.
Someone already pointed out your ram misconfiguration but the video card is also not doing anything for you. Photo editing makes very little use of GPUs. 4GB VRAM is more than enough for this kind of work. 4K video is a different story.

Regarding the i9, it's only 25% faster in Photoshop than the bottom rung basic i5. That may or may not be worth it to you but you should know the real numbers. Lightroom however can use the extra cores and does very well with the i9.

Puget Systems in Seattle publishes FAQ for all types of content creation scenarios and is a good place to start for info. Check out their writeups on Photoshop and Lightroom.
 

hoodafoo

macrumors member
Oct 11, 2020
67
18
Lso Angeles
I put the chips in different configurations and then tested with Geekbench 4 and 5. I liked Geekbench 4 better for testing RAM performance because it would measure RAM bandwidth.

You're welcome to look at my test results: https://browser.geekbench.com/user/338794

Look at the note on each recent test to see my top-to-bottom RAM chip configuration (like 0 32 0 32).

Man, this is such an underrated contribution! In fact, I'd be willing to declare this the LAST word on memory configs on the 2020 if only you were a bit more thorough - where are the numbers for the (32 4 4 32) or (0 32 32 0) 😛

Seriously, good stuff. It affirms what I suspected all along - "RAID'ing" 4 dimms is faster than 2. I was a bit pissed when Amazon Prime day only had 32GBx2 Crucial on sale ($164) because I really wanted 16GBx4 to max out the slots to make use of all the paths
 
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hoodafoo

macrumors member
Oct 11, 2020
67
18
Lso Angeles
Thanks, this is interesting nice job!! Is there a reason you used Geekbench 4? Geekbench 4 is more dependent on RAM and GPU than Geekbench 5, right?

I am mainly interested in the CPU difference since that will be my bottleneck, it seems that in your results the GPU (although I doubt if it's the VRAM, I guess it's the better chip of the 5700XT but I'm no specialist at all) makes the difference like you said, not the CPU. Would that be different in Geekbench 5? There is a relatively substantial difference between the i7 and i9 in the Mac charts there.

Also, in your results, you use two categories. =<64 GB of RAM and > of RAM. Wouldn't it be better two just choose the two configurations people use the most, like 32GB and 64GB? In your =<64 GB category there are probably people who run their benchmarks with 8GB of RAM before upgrading with aftermarket RAM, and that will definitely be a bottleneck right? And I guess nobody with an i7 or i9 is going to stick to 8GB of RAM.

I was really going for the i9 but after weeks of reading about it I may be losing my religion. I would love somebody from Apple explaining why they messed up that beautiful 10th gen i9 opportunity..

Honestly, I wasn't aware of different geekbench versions. I was just happy to get my hands on some data when I stumbled upon those because it identified the processor, OS version, RAM amount and GPU used. How do you even know it was version 4 or whatever?

I basically split into two RAM groups because RAM amounts were all over the map - 8, 24, 32, 48, 64, 72, 128 and it would have been too complicated, plus I would have lost a lot of data samples and some configs were rare. It was meant to give 30k ft view
 

haddy

macrumors 6502
Nov 5, 2012
344
100
NZ
In a couple weeks (saving my pennies) I plan to order a new 2020 27" iMac to replace my mid-2011 (4 core i5). I have a question/ looking for opinions...


What I know I'll be getting:
  • One of the top-tier processors
  • 5700 XT 16GB Radeon graphics.
  • 8GB memory (and buy additional 64GB at OWC).
  • 1TB SSD (99% of my working photos and videos are stored on external drives).
  • Keyboard with added number pad
  • Magic Mouse (No interest in the Magic Track Pad - I have a 1st gen track pad and never use it)
  • 10GBit Ethernet
  • Final Cut Pro X
Does anyone here know how to check if you have 10Gb ethernet using "About this Mac"?
At the moment we just have 1Gb internet speed available but next month we will be getting up to 10Gb. I have just bought my 2020 27" iMac with 10Gb ethernet but I'm not sure where to find out if I have actually got it.
 

TheJuice89

macrumors newbie
Sep 27, 2020
13
3
Honestly, I wasn't aware of different geekbench versions. I was just happy to get my hands on some data when I stumbled upon those because it identified the processor, OS version, RAM amount and GPU used. How do you even know it was version 4 or whatever?

I basically split into two RAM groups because RAM amounts were all over the map - 8, 24, 32, 48, 64, 72, 128 and it would have been too complicated, plus I would have lost a lot of data samples and some configs were rare. It was meant to give 30k ft view

Because of the scores I saw on different places: 2020 iMac i9 scores of Geekbench 5 are around 9-10.000, Geekbench 4 around 45-55.000. You can check the https://browser.geekbench.com/, and click on 'search results' under the Geekbench 4 or 5 tabs on the top left. How did you find the results you posted about? Through the downloadable program itself?
 
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