All this talk of cooling issues, I had no idea it was a problem before joining this forum. It’s got me worried now. My old 2011 iMac is totally silent. I’ve heard the fan once I think.
My ex 27" Late 2013, too, made noise quite rarely, but just about from that moment, a rather large increase in power began with zero improvement of the cooling system. Perhaps now is the very critical moment when they will have to solve it somehow and for the next 5-10 years.
2. Half true. A Pro chip could also be in a mobile form factor. The designation isn't only for desktop. It could be for mobile workstations too.
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Being Apple, I would upgrade the iMac Pro with a Radeon VII. I don't know if it's already discontinued, but this would have been a nice GPU in the iMac Pro while waiting for RDNA2.0
Of course you're right, the Pro version can be mobile too. I may not have put it well.
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As for Radeon 7, this solution already exists in Mac Pro in the form of Vega II. If you look closely, then this base from 7 is also modified by order of Apple. I don’t know how realistic this is for iMac Pro, but I would also be glad to see it there, but not at that price
AMD has RDNA1.0 GPUs in massive stocks.
To be honest, for me personally it would be ideal if they kept their horses for a few more months and waited for the release of Mac with RDNA2, so as not to wait another year or more later.
The 5000 series is excellent, yes, but I must admit that it works at the performance level 56/64 which has been 3 years old ...
As said before I shared your opinion about the latest GPUs in iMac but pldelisle wrote that they all are mobile GPUs and surely when I checked they are. The description for
Radeon Pro 580X, Pro Vega 48,
56 and
64 says "professional mobile graphics chip". Look for yourself.
I guess we could call them Apple specific GPUs, neither mobile or fully desktop, because Apple always orders and puts special GPU models in their computers to satisfy their special needs. It doesn't matter but I'm still sure that iMacs with the same GPU as MBP can perform better because of larger chassi and better cooling, hence faster clocked GPU. Here is a comparison. A 21.5" iMac 2019
Radeon Pro 560X is 2x faster in Unigine than a MBP 15" 2018 with
the same GPU. Therefore I don't think it's completely fair to judge the performance of a new rumored iMac with Radeon 5500 by looking at a MBP with the same chip.
Of course, you are right about the custom versions of the cards assembled by order of Apple. By the way, there is an opinion that this was the key reason why Apple completely switched to AMD, and not to Nvidia, because the latter did not want to satisfy Apple's specific requests.
However, I have doubts about the reliability of the information on Techpowerup. I searched the AMD website for information and did not find anything that Vega Pro 48/56/64 are mobile solutions. Moreover, on other resources I also did not find such a mention, so this may be solely the opinion of Techpowerup. Perhaps they are considering a lower core frequency, which is typical for Pro cards, as a mobile solution by default?
As for the greater power of the videocard, maybe you are right, but maybe not. Are you not worried that the same 560 GPUs, (ok, perhaps one more stripped down for a laptop) have a performance difference of
2 times?
Have a look at the link that you gave with Unigen test on iMac 21.5: Does the Radeon 560X from iMac 2019 have a performance
2.5 times greater than the Radeon 560 from iMac 2017 (1679 vs 669)? How can it be?
And in the Unigen test with the MacBook Pro, how can it be that the Vega 20 is
30% more powerful than the Vega 48? By the way, they themselves write that they do not know why it happened.
I believe that those who did these tests were very wrong somewhere. Or they used different Unigen settings for each device. For example, a native display resolution was applied for each computer - this is the only way I can explain such results, but this is also a gross mistake in conducting comparative tests.