hi guys i have a question does anyone know why the 2013 iMacs dont have supoort for Big Sur i was just curious because the 2013 Macbook Pros seem to be supported. If anyone could please reply back. I would appreciate it. Thanks
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Late 2013 imac 21.5in Macos Big Sur question
- Thread starter Jordan246
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The 2013 MacBook Airs are also supported, So I find this rather bizarre.
Thats what is stumping me because the 2013 macbook pros have the same nvidia gt750m graphics card thats in the 2013 imacs only with one gb less vram
And yet the mid-2014 21.5” iMacs (which had very basic specs, and were rather unpopular) will be supported. I just did some research on it and got a feeling this may be due to the fact that the 2013 21.5” iMac used PC3-12800 DDR3 RAM while the mid-2014 one (that hardly anyone got) used LPDDR3 SDRAM (also used in the 2013 MacBook Airs and Late 2013 MacBook Pros).
Both 21.5” iMac models were sold until October 2015.
Both 21.5” iMac models were sold until October 2015.
Reasons why I think the 2013 iMacs aren't supported:
The higher end 21.5" late 2013 iMacs use 750Ms, except that they only have 1GB of VRAM compared to 2GB on the MacBook Pros from the same era (as well as the 2013 Mac Pros which had anywhere from 4GB-12GB of VRAM depending on which model of dual GPUs you picked), which is possibly why those specific 2013 iMacs are not supported. They probably wanted to drop anything with 1GB of VRAM or less in it and that happened to include that iMac model. Every 2012 Mac that was dropped either had 512MB or 1GB VRAM.
However, the 27 inch has 2GB of VRAM and a GTX 755 so I have no idea why that was dropped. They probably dropped those too because they wanted to keep some form of "consistency" or something (I know this sounds stupid but I honestly see Apple doing this).
As for the Iris Pro 5200 only 21.5" iMacs, they're more powerful than the low end 1.4GHz HD 5000 2014 iMacs and yet they're not supported. There's nothing that they are missing that the 2014s have, so it's obviously arbitrary in that case. I think the only reason why they dropped the low end 2013s as well is because they didn't want to make the higher end 750M iMac look bad by getting less software updates than the Intel Iris Pro 5200 ones, so they cut both off.
The higher end 21.5" late 2013 iMacs use 750Ms, except that they only have 1GB of VRAM compared to 2GB on the MacBook Pros from the same era (as well as the 2013 Mac Pros which had anywhere from 4GB-12GB of VRAM depending on which model of dual GPUs you picked), which is possibly why those specific 2013 iMacs are not supported. They probably wanted to drop anything with 1GB of VRAM or less in it and that happened to include that iMac model. Every 2012 Mac that was dropped either had 512MB or 1GB VRAM.
However, the 27 inch has 2GB of VRAM and a GTX 755 so I have no idea why that was dropped. They probably dropped those too because they wanted to keep some form of "consistency" or something (I know this sounds stupid but I honestly see Apple doing this).
As for the Iris Pro 5200 only 21.5" iMacs, they're more powerful than the low end 1.4GHz HD 5000 2014 iMacs and yet they're not supported. There's nothing that they are missing that the 2014s have, so it's obviously arbitrary in that case. I think the only reason why they dropped the low end 2013s as well is because they didn't want to make the higher end 750M iMac look bad by getting less software updates than the Intel Iris Pro 5200 ones, so they cut both off.
But for the person who bought a 21” iMac in early to mid 2015, they would have had the option of a 2014 1.4GHz, or late 2013 2.7GHz or 2.9GHz model. Never in my wildest dreams would I have thought that the more expensive products than others in the same series (e.g. iMac14,x vs iMac14,y) would have been denied such a critical hardware refresh in 2014 (even if minor) if it meant an additional 1-4 years of additional OS support were at stake. Great way for Apple to lose the respect of some of its best customers IMO.
Quite messed up that Apple did that. On the higher end iMacs, the Iris Pro GPU is actually disabled because it isn't really needed in a desktop. The 750M also doesn't take any system RAM which is actually a bad thing because it's stuck at 1GB. The Iris Pro takes up to 1.5GB of system memory (leaving you with either 6.5GB on 8GB RAM Macs or 14.5GB on 16GB RAM Macs), plus it has 128MB of memory on board. Because of the VRAM situation and partially because of business practices Apple likes to do, ALL the 2013 iMacs got cut off prematurely even if some of them either had 2GB of VRAM in their GPU (27 inch iMac) or only had Iris Pro graphics (the 2.7GHz 21 inch).
I think this is the first instance of a Mac I've seen where the lowest end model (the 2014 1.4GHz iMac) is actually getting more support than the more expensive late 2013 iMacs! I'm curious to see why Apple didn't put 2GB of VRAM in the GPU on the 21 inch iMacs even if not retina.
It's actually a weird situation. The closest thing Apple did before was drop the iPhone 6/iPod touch 6 with iOS 12 and keep the iPad mini 4 supported up to this day. That was also because of the iPhone and iPod touch only having 1GB of RAM while the iPad mini 4 has 2GB.
Edit: I think I figured out why the 27" iMac is unsupported as well. Apparently, the low end 755M configuration only comes with 1GB of VRAM as well (all others have at least 2GB). However, the higher end models have no excuse not to be supported.
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I actually owned a Late 2013 21.5" iMac until last year when I "upgraded" to a Late 2015 21.5" iMac. So this news makes me worried especially considering that the 2014 and 2015 iMac's are either worse or only slightly better than the 2013 models. How likely is it that Apple will stop supporting the 2014 and 2015 iMacs in a year?
2013 Mac Pro was on the market until last December. Apple has historically supported their discontinued macs (with the exception of Xserve G5) with software updates for a minimum of three years. So my thoughts are that Apple is unlikely to drop any more macs until 2022. At that point, I’m thinking that the next macs to lose support will be those capable of making a chime sound on startup.
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I currently own a Late-2013 iMac CTO with a 3.5GHz i7 and GTX 4GB 780M graphics. Wondering if attempting to update to Big Sur, Apple will simply "look" at the model identifier rather than the specs and deem mine incompatible (which would be BS).
I was planning on finally updating my iMac now, but not sure if I want to be an early-adapter of the new Macs (or if even the iMac will be the first set of computers to receive the new Apple chips) versus purchase an Intel-Mac, and have it become obsolete in short order.
I was planning on finally updating my iMac now, but not sure if I want to be an early-adapter of the new Macs (or if even the iMac will be the first set of computers to receive the new Apple chips) versus purchase an Intel-Mac, and have it become obsolete in short order.
Apple as of late has only dropped Mac models every other year (10.12, 10.14, and 11.0). I think the 2022 macOS will drop Haswell because all the models will have been discontinued for three years, and require Skylake or USB-C.
Just noticed something else!
The Haswell Processors in the Late 2013 21.5" iMac do not support hyperthreading, while those in the Mid 2013 MacBook Air, Late 2013 MacBook Pro, 2014 Mac mini and Mid 2014 21.5" iMac do support hyperthreading and use low power LPDDR3 RAM that is soldered and can't be upgraded at all. 2013 Mac Pro CPU also supports hyperthreading.
I'd be surprised if these things had nothing to do with it.
As for the Late 2013 27" iMacs vs newer 27" iMacs, someone else might know but perhaps Apple simply didn't want to support large non-retina displays. I'm really not sure what happened there.
The Haswell Processors in the Late 2013 21.5" iMac do not support hyperthreading, while those in the Mid 2013 MacBook Air, Late 2013 MacBook Pro, 2014 Mac mini and Mid 2014 21.5" iMac do support hyperthreading and use low power LPDDR3 RAM that is soldered and can't be upgraded at all. 2013 Mac Pro CPU also supports hyperthreading.
I'd be surprised if these things had nothing to do with it.
As for the Late 2013 27" iMacs vs newer 27" iMacs, someone else might know but perhaps Apple simply didn't want to support large non-retina displays. I'm really not sure what happened there.
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Here's the issue with that theory though... a quad-core processor without hyperthreading is better than a dual-core processor with hyperthreading because it is more powerful and can take advantage of more resources. Two physical cores being added is better than adding two that are simply virtual and rely on the other cores (aka hyperthreading).
I really suspect that it's the GPU VRAM limitations as the 21 inch 2013 iMacs were the only Macs left (along with 2012-early 2013 MBPs and 2012 iMacs) to have 1GB VRAM or less (as well as the base 27 inch iirc). A few of the 27 inch 2013 models had 2GB or more, and the Iris Pro only 21 inch models actually had 1.5GB VRAM because of the system RAM sharing.
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Actually, having thought about it more, it seems the two minimum requirements for Big Sur are
- 802.11ac Wi-Fi
- 1.5 GB VRAM
Hi there! Some people say the Late 2013 iMac (14,1/14,2/14,3) did not make the cut for the eventual abysmal Fusion Drive performance. This does not make much sense IMHO, since the Mid 2014 iMac (14,4) would have to have exactly the same problem, as I suppose it shares its motherboard (Except for the soldered Dual Core CPU and 8GB RAM), 2nd Gen. Blade PCIe SSD and 1TB HGST SATA HDD with the Late 2013 models.
Regarding the 1.5 GB VRAM requirement, it seems to be what Apple could use as THE technical "excuse". But I wonder whether the Mid 2013, Early 2014 and Early 2015 MacBook Air (6,1/6,2/7,1/7,2), Late 2013 MacBook Pro 13" 128GB (11,1) and Late 2014 Mac mini (7,1) with theirs Intel HD5000/6000/Iris5100 and only 4GB of RAM would generally use more than 1GB as VRAM - Leaving less than 3GB of System RAM available...?! Besides, even if less important, let's not forget the discrepancy in VRAM bandwidth, 12.8-25.6GB/s for Intel HD/Iris (DDR3) vs 80-160BG/s (GDDR5) for the NVidias. Moreover, 1GB of VRAM fully available to drive a 1080p (iMac 14,1/14,3) or even a 1440p (14,2) Display is more VRAM/pixels than 1.5GB to drive a MacBook/Air/Pro Retina Display or 2GB to drive an iMac 4K/5K one.
One more thing (to think of)... It seems the Late 2013 iMacs (14,1/14,2/14,3) are the only unsupported Macs with the latest BootROM version 430.0.0.0.0 as of Catalina 10.15.7 (And Big Sur 11.2.3). All other Macs sharing this BootROM version are officially supported: iMac 14,4/15,1 - MacBook Air 6,1/6,2 - MacBook Pro 11,1/11,2/11,3 - Mac mini 7,1. Strange indeed. I have no idea about the different SMC versions though.
Everything said... It does not make much sense (IMHO) supporting the lowest end iMac 14,x model and cut all others.
Go figure... Cheers!
Regarding the 1.5 GB VRAM requirement, it seems to be what Apple could use as THE technical "excuse". But I wonder whether the Mid 2013, Early 2014 and Early 2015 MacBook Air (6,1/6,2/7,1/7,2), Late 2013 MacBook Pro 13" 128GB (11,1) and Late 2014 Mac mini (7,1) with theirs Intel HD5000/6000/Iris5100 and only 4GB of RAM would generally use more than 1GB as VRAM - Leaving less than 3GB of System RAM available...?! Besides, even if less important, let's not forget the discrepancy in VRAM bandwidth, 12.8-25.6GB/s for Intel HD/Iris (DDR3) vs 80-160BG/s (GDDR5) for the NVidias. Moreover, 1GB of VRAM fully available to drive a 1080p (iMac 14,1/14,3) or even a 1440p (14,2) Display is more VRAM/pixels than 1.5GB to drive a MacBook/Air/Pro Retina Display or 2GB to drive an iMac 4K/5K one.
One more thing (to think of)... It seems the Late 2013 iMacs (14,1/14,2/14,3) are the only unsupported Macs with the latest BootROM version 430.0.0.0.0 as of Catalina 10.15.7 (And Big Sur 11.2.3). All other Macs sharing this BootROM version are officially supported: iMac 14,4/15,1 - MacBook Air 6,1/6,2 - MacBook Pro 11,1/11,2/11,3 - Mac mini 7,1. Strange indeed. I have no idea about the different SMC versions though.
Everything said... It does not make much sense (IMHO) supporting the lowest end iMac 14,x model and cut all others.
Go figure... Cheers!
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They probably stopped supporting those iMac’s because of the NVIDIA graphics cards in them. Now that they’d dropped Intel and Intel has responded with scathing ads, I suspect that all Intel computers will be on the chopping block sooner rather than later. Already worried for my late 2015 21.5” iMac.
The supported Late 2013 / Mid 2014 15" MacBook Pro 11,3 have exactly the same NVidia GT750M, but with 2GB VRAM. Notice however those 2GB of VRAM drive twice the pixel count of a 1080p Display.
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Fortunately for us the folks behind OCLP have our backs and my 2013 21.5" is running Monterrey swimmingly. I would recommend some flash storage for the journey.
