Even if an individual application doesn't use more than 8 cores, it doesn't mean those cores aren't useful. Most people run multiple apps. Developers might run multiple VMs or Docker containers or a Kubernetes or Hadoop compute cluster. More cores are definitely better for that use case.
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Decision time i7 vs i9 for new 2020 iMac?
- Thread starter BasilFawlty
- Start date
- Sort by reaction score
Even if an individual application doesn't use more than 8 cores, it doesn't mean those cores aren't useful. Most people run multiple apps. Developers might run multiple VMs or Docker containers or a Kubernetes or Hadoop compute cluster. More cores are definitely better for that use case.
I agree it’s probably diminishing returns. I’m also wavering over the increased wattage and thermal output of the i9. Am pretty settled on the 5500XT for that reason.
I'm in the same boat. I, too, do a lot of RAW photography processing with Lightroom and Photoshop, and am in the market for a new iMac. I've been using Lightroom on my work iMac for about 6 months. It's a 2019 iMac, 8-core i9, 64 GB RAM, 2 TB SSD, Radeon Pro 580X 8 GB. I can tell you that Lightroom takes full advantage of all 16 threads during import (copying, building previews, etc). I've actually seen Activity Monitor at 1600% for Lightroom. Other than that, it will make use of the 8 cores as it needs (8 threads, not 16), but it's quite hard to fully tax all of them at once. Lightroom doesn't use the video card at all in the current version. (Lightroom Classic and Lightroom perform the same for me.)
Is faster import that important to you? I'm torn, personally. The fast internal SSD already makes everything so fast. By the way, I hope your catalog and preview files are on the internal drive? It's SO much faster than any external SSD. On that note, I would recommend an external PCIe enclosure with superfast internal NVME like the Samsung m.2 970 Evo Plus. It connects via USB-C.
I know After Effects can easily use *full* GPU and *full* CPU, but not sure about Final Cut Pro X. If you do much work in Final Cut Pro X, I would *guess* you would enjoy a lot of the speed boost with the higher end machine.
Like I said, I'm torn, too. I know the higher end one would be fast, and that would be nice, but for me, my personal machine is just a hobby that doesn't make me any money... do I really need to spend that much? lol
I think in 5-6 years I would rather have the 2 TB internal SSD than the i9. I'm not an expert on SSDs, but i'm not sure if an external SSD will ever be as fast as Apple's internal SSDs.
If you're brave enough to crack it open, CPU is socketed.
I am purchasing the i7 5700 XT because the i9 just isn’t worth the extra $400. Watch MaxTech’s videos and it will prove to you that you should just buy the i7.
Max also covers the 10 core 5700 XT Model in another video and also covers gaming performance in another video as well!
Regarding the Nano-texture screen, please see this thread: https://forums.macrumors.com/threads/worth-getting-the-nano-display-on-the-new-2020-imac.2248657/
Totally agree.
When I need to crunch a lot of data, believe me, more cores help!!! Still far from what AMD can offer. 10 cores is almost standard today for such a capable machine. AMD consumer grade CPUs are available up to 16 cores. It’s 12 threads more than what’s possible in the iMac for not *that* much more regarding price. Apple silicon will likely beat Intel cores count on first iteration too. For a power user, 10 cores is far from being too much. It’s just a normal core count. We had quad core CPU in high end computers for 7 generations ....!!!!!!! Having the exact double of that in current high end is almost shameful.
The iMac isn’t far from being a workstation class computer. It has plenty of power to do so. Cooling might be less than iMac Pro but CPU consumes less power too. Number of Thunderbolt 3 ports is limited by CPU number of PCI-E lines (so by Intel). Apple really milked it the best they could with consumer class Intel CPU.
Last edited:
MaxTech has both videos and it’s not as big of a difference that you might think.
I agree, but don't you get more performance if you have multiple apps open at the same time?
Theoretically yes. You can have more apps at the same time running with one dedicated core.
Anyone that is seriously debating whether you should get the 8 core or the 10 core honestly shouldn’t even be debating it. This years i7 is 20% faster than last years 8 core i9 so clearly it’s more than enough performance for the vast majority of people in this thread and forum. You 100% already know if you need the 10 core model and most likely aren’t even paying for it since it’s under a business account or someone is purchasing it for you on behalf of your workload. Just buy the i7 and save the money towards more RAM or SSD.
Thank you, that made it a bit easier for me to decide. You seem to have superior knowledge to me. I am guessing the i7 also runs more quite and has a higher performance for single-core tasks, am I right?
Hey.
It’s not a one-size-fit-all.
As a data science engineer and software engineer, 2 cores more make a freaking huge difference.
As I said in my other post, 10 cores in an iMac is just the right thing, and it’s even arriving very very late (thanks to Intel). There are plenty of usages that benefit from additional 2 cores.
Very slightly because it has 200 MHz more on the base clock. Won’t be noticeable.
Last edited:
Could you name a few more examples, where the additional 2 cores would make a big difference?
Sometimes I need to process a ton of 3D medical images. Applying preprocessing. I multiprocess this over the number of threads I have in the machine.
More cores help at running more Docker containers at once without slowdown. So I can test my code faster in staging environment before deployment on compute servers.
When you have data to crunch in a Map-Reduce scheme, having more cores is definitively a plus.
Things like that. I can assume that it’s also beneficial in music production for plugins or when working with multiple tracks.
The i7 does run a little bit quieter but not much honestly compared to the i9. The i7 can sustain a higher clock speed of 4.4 ghz under full load compared to 4.03 for the 10 core. As far as single core they are both identical basically. The i7 benchs at 1266 and the i9 benchs at 1271 I believe it’s super minor.
I never stated it was a one size fits all. What I’m saying is the vast majority of folks debating this topic most likely do not need the 10 core CPU because again you would already knew if you needed a 10 core CPU for your workload. The 8 core i7 is more than enough power.
Here's a rough look at Geekbench 5 averages taken yesterday between the two 2020 processor options in question. I just dropped the first five pages (125 scores) into a spreadsheet and took the median values of each, I didn't control for the amount of RAM in the machines or any other spec differences:
Last edited:
I can't understand why the i9 has a higher single-core score, since the clock speed in general and under full load is lower. Does anybody have an explanation?
Disclaimer: I know nothing about this kind of tech, but the i9-10910 has 20MB L3 Cache versus the i7-10700K's 16MB L3 Cache and also has a lower 95W TDP compared to the i7's 125W TDP... Does that make a difference when it comes to this stuff? I don't know!
EDIT:
**See posts #76 and #80 for better information about this**
Last edited:
Very slightly for the cache.Disclaimer: I know nothing about this kind of tech, but the i9-10910 has 20MB L3 Cache versus the i7-10700K's 16MB L3 Cache and also has a lower 95W TDP compared to the i7's 125W TDP... Does that make a difference when it comes to this stuff? I don't know!
Apple probably programmed the i7 TDP to match 95w instead of 125w. The iMac cooling system is made for 95w cpu.