Just received my new 2020 iMac. I have the top level 27" so it has the Core i7 and radon 5500xt card, I upgraded the SSD to 1TB. I upgraded the memory to 40gb with my own memory, and nothing else. I am replacing my Mid 2017 27" imac with an upgraded 4.2 GHz i7 processor, 2TB Fusion Drive and a Radon pro 580 and 16GB of memory. Once set up, I tested the display and video card. I ran a 4K UHD video of the virgin islands. Side by side on my desktop. There is a noticible difference in the video quality. I was hoping I would see a better image on the new machine but that did not happen. The older iMac has a noticeably better image. It is deeper in color and much crisper. This is very noticable. I check the settings I could find on the display and the are identical between the machines? Any thoughts or suggestions?
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2020 27" iMac Help
- Thread starter Macster389
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Yes I also turned off the True Tone. Spoke to an Apple tech support guy this afternoon and believe it or not he looked up the specs on my old machine and new machine and basically told me I have a better video card in the old machine. He said it was not a big difference but even though the newer card is a good one it is not quite as good as the old card that is three years dated. He said I would need to pay for one of the upgraded cards to have a better video card. Can you believe it you buy a top-of-the-line iMac and it’s not as good as the top-of-the-line iMac from three years ago as far as video clarity in 4k
This sounds like complete BS. I have the same 2020 iMac and 4K videos are perfect. There is something else going on.
Try this in 4K, but you need to do in Chrome, as Safari currently does not currently do 4K youtube:
Also turn off extended dynamic range as this is not currently functioning properly in MacOS Catalina:
System Preferences
Option-click on the Displays icon
Uncheck "Allow extended dynamic range"
(Refresh the web page after unchecking this)
Edit: also try downloading this 8K video from NASA, and play it using quicktime. On my machine (same as yours, i7 and 5500XT) it plays perfect, and the GPU usage is less than 10%:
(Right click on the web page and "download video")
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When I say top of the line they offer three different basic models of the 27 inch. I have the top configuration without adding higher grade processor or video card. My mid 17 is the same way except I did upgrade the processor to the i7 but it was the standard video card offering for that unit I did not upgrade the video card
I get it seems like there should be some other issue. But if you look at the specs of the radon pro 580 and the current 5500 XT it is quite eye-opening. While this is a newer card it seems the older card was actually a better offering for that timeframe. It seems like Apple could have offered a better card. And I agree that people see things differently but when screens are side-by-side and there is fairly big differences in them, either the machine is not performing or there is something in settings that needs to be fixed. Thanks
In 2017 radeon pro 580 was the top GPU (for iMac), whereas in 2020 the 5500XT is the 3rd from top GPU. So Apple does indeed offer two better cards (5700 and 5700XT).
According to this, they are similar, with some specs higher and some specs lower:
In any case, for just playing 4K video it is much more than adequate.
Hope this helps, and hope you can find the issue causing the apparent poor video quality.
But I understand your point: that one could expect the 5500 XT from 2020 to be significantly better than the 580 from 2017.
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My point was the 580 was includeed in the top level factory build without having to pay for an upgraded card! In the 2020 they chose to start off with a lower quality card compared with mid 2017. The only reason I am upgrading is.....because I had an 09 iMac that I used until I bought the mid 2017. The upgrade was a little painful as some of the software and programs were just too outdated and I was stuck on a 3-4 generation old operating system. So I have decided to upgrade my computer every 3-5 years and do a trade in on the old unit. This will keep me more current. But the video is just not as good as my older machine and I did not want to pay an additional 300 to get the 5700 card. If apple had done the same thing in 2020 as they did in 2017 the 5700 would be the standard card in my 2020. I will send this back and see what happens in 2021. The 8K video posted above plays great on my 2017. Very smooth video!
Just had a chance to watch. Still definitely runs better on the 2017 so.....the 2020 is going back tomorrow. Thanks for posting the video.
I am using the exact same spec'd 2017 4.2GHz iMac as you, except with 40GB of RAM.
In fairness, it was a CTO model and there was a choice between the Radeon Pro 575 (4GB VRAM) and the pricier Radeon Pro 580 (8GB VRAM).
On mine as well.
This is incorrect as of Big Sur. You can watch 4K content on Safari by enabling 'VP9 SW decoder on battery' under 'Develop' -> 'Experimental Features'.
Can not find my build email but I thout the 3 27" models had a Radeon Pro 570, 575 and 580 respectively on the three models. I did not remember upgrading the card. I did upgrade to drive to the 2gb fuzion and the i7 upgrade.I am using the exact same spec'd 2017 4.2GHz iMac as you, except with 40GB of RAM.
In fairness, it was a CTO model and there was a choice between the Radeon Pro 575 (4GB VRAM) and the pricier Radeon Pro 580 (8GB VRAM).
On mine as well.
The 4.2GHz CPU was only available in Configure To Order and Apple offered a choice between the Radeon Pro 575 and 580. See here for the details. If you ordered it directly from Apple then you had to have chosen the 580 as an upgraded option.
This machine is still a workhorse and getting it done for my needs. I'm waiting for a full redesign before I'll be upgrading.
Just found this and it shows the 580 with the standard build and the 3.8GHz processor. https://techable.com/apple/specs/imac-3-8-ghz-intel-i5-27-inch-mid-2017/
I watch 4K on Safari/YouTube all the time (since updating to Big Sur), but I don't have this feature enabled.
Thanks for confirming that. Indeed, it seems that the high end 3.8GHz i5 model did come with the Radeon Pro 580. Everymac confirms this to be the case as well.
But as I mentioned above, the 4.2GHz i7 was only available from Apple as a CTO and the Radeon Pro 575 was offered as the default GPU for purchase. The 580 was an upgrade although I've forgotten the exact amount. I think it may have been +$200.
You surely have the 'VP9 decoder' enabled on your Mac, which I forgot to mention in my previous post. I think that old machines don't have these features enabled by default (and I do remember ticking 'VP9 SW decoder on battery' on my 2015 Macbook Pro as I wasn't able to watch 4K while on battery). This was also mentioned in today's article: https://www.macrumors.com/2020/12/07/macos-big-sur-useful-features/ (point #4).