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I have a late 2013 27" iMac I recently purchased as a backup as my M1 MacBook was bein repaired. I have since installed Open Core Legacy and Ventura on it. It works perfectly well, albeit

1. The GPU (Kepler) is a limiting factor, being Thunderbolt 1/2 compatible it makes it difficult to do anything in terms of using an EGPU.

2. I had thoughts of putting a 16 core Xeon Haswell CPU in it but it seems it's firmware locked to a specific range of CPUs has anyone had any luck with work arounds?

3. Regarding RAM it has 16gb with two 8gb chips in each channel. I w as thinking about upgrading to 32gb as RAM is cheap.

4. It comes with a 512gb internal SSD. Although it has a NVME port, has anyone had any luck installing Open Core with Ventura or Sonoma on an NVME drive instead?

5. I know I won't get performance anywhere near my M1 Mac, although, the performance is quite good, the limiting factor seems to be the 2GB 775m (Kepler based) GPU. I doubt finding a 4GB 780 logic board would make any difference either?

My other option for this Mac would be to get a Thunderbolt 3 to Thunderbolt 2 adapter and just use it as an external display for my M1 Mac using Target Display mode albeit this seems to be a bit of a waste. I would have liked to have swapped in a 16 core Xeon but it seems this is limited to other Macs such as the cheesegrater and trashcan models....

You can get some stupid cheap Xeons like the Xeon E7 8890 and others for $50 in DDR3 models but it doesn't seem like it would be recognised by Open Formware unfortunately. I could do the swap myself but from what I gather I would just end up with a Mac that doesn't boot.
 
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Juicy Box

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Sep 23, 2014
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Updating the RAM is super easy on the Late 2013, if you can get it for really cheap, might as well.

You can use external drives on the Late 2013 with decent speeds to avoid opening the iMac.

It comes with a 512gb internal SSD. Although it has a NVME port, has anyone had any luck installing Open Core with Ventura or Sonoma on an NVME drive instead?
I haven't used Open Core, but would suspect a third-party drive to operate the same way. I have seen weird bugs before with people that replaced their OEM blade SSD with a third party NVMe, but not necessarily related to Open Core.

If you are worried about using an internal NVMe and you want to still have an internal solution, your iMac has an unused SATA port for a HDD. I have replaced the HDD in a few Late 2012 and Late 2013 iMacs with SATA SSDs, and they run great.

My other option for this Mac would be to get a Thunderbolt 3 to Thunderbolt 2 adapter and just use it as an external display for my M1 Mac using Target Display mode
It won't work.

The Thunderbolt iMacs that are capable of Target Display Mode (like your Late 2013) will only work with other non-AS Macs with Thunderbolt.

The only iMacs that you can use Target Display mode with your M1 MacBook is the Late 2009 to Mid 2010 27" iMac, and this is done using a USBC to Mini DisplayPort adapter/cable.

The Late 2009 to Mid 2010 27" iMacs can be used with non-Macs or even non-computers as well as long as the device outputs with DisplayPort.


Sucks that Apple didn't add support for Target Display Mode on newer iMacs, and well as allowing AS to be used with older TDM capable iMacs. Just a waste to throw away a decent monitor that looks nicer than most modern monitors that you can get off the shelf at a local Best Buy.
 
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MacMore

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Updating the RAM is super easy on the Late 2013, if you can get it for really cheap, might as well.

You can use external drives on the Late 2013 with decent speeds to avoid opening the iMac.

I noted how cheap that DDR3 RAM is now, and given the amount of slots it has it would be fun to populate the other two banks for 32gb of RAM. I'll be doing that upgrade this week. If nothing else I'll set it up later to serve a Windows 10 install so I have one I can use screen sharing with should I need to do anything Windows based. You can only virtualise Windows 11 on M1, M2, M3, and that's a dog's breakfast which has its own "Rosetta" to run x86 apps which may not be guaranteed to work.


An external NVME pending prices is the easiest option. These machines are a pain in the arse to open up and were when they were new needing suction to remove the glass screen protector. That's more of a check this space with regard to prices.



As to the CPU, I don't understand why they do that, but its firmware locked, the 4770 is not really a huge performance boost. The extra cores would have been nice if I could have fitted a Xeon but its not possible it seems. Unfortunately you can only fit Xeons to the trash can, and cheese grater models of Macs and I'm not going down that path of spending another $500 on a legacy Mac at this point.


Now my M1 Max MacBook is back, I will fiddle with this thing, wipe it and install Sonoma. M1 is a different kettle of fish. Just as a quick benchmark. I go from 100fps on low in Minecraft in 2560 resolution to 100fps with all settings and shaders maxed out at 3024 on my M1, and the editing time for 4:2:2 clock vs clock is roughly 5 times as fast on M1 as compared to the 7th generation iMac.

I don't understand how exactly, because while the source for BSD and Linux Nvidia drivers is available. I'm sure that's not not what they are using, but... performance under Open Core Legacy under Ventura seems to be marginally better than it was on Catalina. The video performance seems to be marginally better with Ventura installed on the iMac.

I'll start by grabbing some RAM and filling it out to 32gb, which will be useful should I need to do some rendering.

The main bug I've noticed with Open Core s that sometimes when you quit audio apps such as Spotify the audio driver crashes the computer.

There were some minor cosmetic issues playing Minecraft with missing textures completely. I suspect that's more to do with the age of the Kepler based 775m rather than the Mac OS itself.

Other than the above the speed of Ventura is slightly better than Catalina, and I'm sure Sonoma will be better again due to internal bug fixes. I don't use any of the hand off features with Mac OS so I haven't noted any Continuity bugs.

I don't sleep any of my Macs either, especially since they run solid state drives. The only thing I sleep is the screen, so I haven't seen any wake from sleep isses.

Overall I would recommend upgrading to the latest Mac OS version you can, especially if you plan on having it connected to the internet. Security patches are essential, and the bug fixes and software improvements are notable.

While its similar enough there is so much missing from the classic OS X experience that is Catalina that you really don't know until you run it alonside Sonoma. Dark mode alone is worth it.
 
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Juicy Box

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Sep 23, 2014
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These machines are a pain in the arse to open up and were when they were new needing suction to remove the glass screen protector.
I have opened almost every one of my Macs over the years, and just iMacs alone, I have replaced the internal drive(s) in the G3, G4, G5, Mid 2007, Mid 2011, Late 2012, and Late 2013 iMacs.

The 2013 isn't really that big of a deal to me, with the exception of cleaning the old glue strips and replacing them. I don't do it anymore on my Late 2012s and Late 2013s. For now on, I am using painter's tape to hold the display on the case. I have already done it to one, a Late 2013, and will do it for the rest.

It is just a pain in the ass cleaning up all the old adhesive, and if you don't do a good job, your display could fall out. So, I am just leaving the old stuff on, and using painter's tape.

I know this won't work for many others, as the aesthetics would Bother them. Either way, I recommend using painter's tape for a few weeks after putting new adhesive strips down, to make sure they stay glued.

An external NVME pending prices is the easiest option.
Easy, but expensive.

You can use TB3 NVMes with your iMac as well, giving you about the same speeds as replacing the internal blade, but this is not very cost effective. If you already had one, it might be worth it.

To prevent having to open up your iMac, a USB3 SSD might be the best way to go if you need more faster storage, but it won't be faster than your internal drive.
 

MacMore

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To prevent having to open up your iMac, a USB3 SSD might be the best way to go if you need more faster storage, but it won't be faster than your internal drive.
Sorry if I wasn't clear, mine has a 512gb SSD in it already. NVME is probably more of a pipe dream. I'd upgrade the CPU but there's no real options beyond a quad core i7.

RAM is cheap though. I think I'm just going to order another 16gb for it and max it out to 32gb.
 

Nguyen Duc Hieu

macrumors 68040
Jul 5, 2020
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Ho Chi Minh City, Vietnam
2. I had thoughts of putting a 16 core Xeon Haswell CPU in it but it seems it's firmware locked to a specific range of CPUs has anyone had any luck with work arounds?

To my understanding, imac 2013 logicboards use LGA1150 CPUs.
The 16 core Xeon you are talking about, if available at all, will feature LGA 2011-3 socket.
Hardware wise, they are not compatible.
 

Juicy Box

macrumors 604
Sep 23, 2014
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To prevent having to open up your iMac, a USB3 SSD might be the best way to go if you need more faster storage, but it won't be faster than your internal drive.

Sorry if I wasn't clear, mine has a 512gb SSD in it already.
No, you were clear on your iMac having 512GB of SSD storage, but what wasn't clear was why you were interested in installing an NVMe drive internally.

I just assumed that the 512GB wasn't enough and you wanted bigger. Which is why I suggested using an SSD over USB, which wouldn't be as fast as the internal storage, but it would be cheap and easy way of getting decent speeds and larger storage.
 

paardenkapper

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Apr 8, 2023
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Just remember that the max TDP of the heatsink is not that great and it may not suffice for a Xeon CPU.
The Xeon E3-1270 has a TDP of 80W for example.

I never cared much for graphics performance on iMacs but it seems that you need Thunderbolt 3 for any eGPU.
 

MacMore

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No, you were clear on your iMac having 512GB of SSD storage, but what wasn't clear was why you were interested in installing an NVMe drive internally.

I just assumed that the 512GB wasn't enough and you wanted bigger. Which is why I suggested using an SSD over USB, which wouldn't be as fast as the internal storage, but it would be cheap and easy way of getting decent speeds and larger storage.

1. I have enough internal storage/

2. I was just thinking because you can get 1150 Xeons for like $50 now for insane levels of performance with multi threaded apps it would be possible to drop one in. But it''s EFI locked (which is stupid). Prior to Intel Mac there was no EFI (Open Firmware CPU lock). There were quite a few custom server options that used Xeons on the same socket. Sandy Bridge (Haswell) era i7s are OK yeah.... but it has about about a 10th of the speed of my M1 Max, let alone an M2 or M3. That would have been less of a question if I could have gotten my hands on a Xeon chip instead. When apps are optimised for them they perform quite well... Even today.... such as a Xeon E3-1245.

3. If it were possible then it might be interesting to stick an NVME drive in the spare slot.

None of this is possible, so all I have done is ordered more RAM.

I have absolutely no idea what to do with this iMac now. I may just load it up as a server now my MacBook is back to hand out whatever over the network.

I have no interest in sitting in front of a desktop/all in one.
 
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Nguyen Duc Hieu

macrumors 68040
Jul 5, 2020
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Ho Chi Minh City, Vietnam
Here in Ho Chi Minh City, I bought
Xeon E3-1246 V3 = 25$~30$
Core i7-4790 = 35$~40$
I'm surely don't want to spend 30$ just to save 10$, under the high risk that a Xeon is not compatible.
Just go buy the core i7 from the begining. Save myself the headache.
 

MacMore

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Here in Ho Chi Minh City, I bought
Xeon E3-1246 V3 = 25$~30$
Core i7-4790 = 35$~40$
I'm surely don't want to spend 30$ just to save 10$, under the high risk that a Xeon is not compatible.
Just go buy the core i7 from the begining. Save myself the headache.

Not all of us live in China. Also it underscores the missing point:

Out of all the stupid **** Apple does EFI locking specific machines to specific CPUs is among the most stupid.
 

Nguyen Duc Hieu

macrumors 68040
Jul 5, 2020
3,016
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Ho Chi Minh City, Vietnam
Not all of us live in China. Also it underscores the missing point:

Out of all the stupid **** Apple does EFI locking specific machines to specific CPUs is among the most stupid.

Not just Apple, kid.
HP does the same thing, Dell sometimes, too.

Out of China, (I'm living in Vietnam, though), like in the US, you might obtain them even cheaper. Like from the dumpster or from the Salvage Army stores.


Or ebay....
 

MacMore

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I realised after I posted this that calling Vietnam China was obnoxious but I did it by mistake. I live in Australia, we are a small market....Your retort is irrelevant to me.

Go watch some videos on the performance of 8 and 10 core Xeons when multithreading is accounted for in apps that support it and then get back to me. There is reasoning to do things...

In hindsight this is why people still use Mac Pro's in 5,1 and 6,1 configuration. But then this iMac was always a stop gap and I didn't feel like having to buy a monitor and all the rest of the crap involved.

On a level of technicalities it is correct that Vietnam is China historically, but then it would piss a lot of people off in Vietnam to call it that now...

You probably can't get it cheaper due to the large amount of surplus/used PC parts suppliers/markets in that part of Asia in the West either AU or US.

Ironically I buy a lot of old used tech out of Japan for this reason, it's simply cheaper even when accounting for shipping costs. That coupled with the fact that given that Australia is a small market there isn't exactly a plethora of second hand parts just laying around.

When there are second hand parts available you generally have to catch an education department that is throwing their old computers in the dumpster... It doesn't work like that here.... if at all...

Like I said I thought I could do something interesting and then I realised that EFI is stupid when it is abused in the way it is to lock CPUs to computers under the guise of "security" but here we are today dealing with this **** issue.
 
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Nguyen Duc Hieu

macrumors 68040
Jul 5, 2020
3,016
1,006
Ho Chi Minh City, Vietnam
I realised after I posted this that calling Vietnam China was obnoxious but I did it by mistake. I live in Australia, we are a small market....Your retort is irrelevant to me.

Go watch some videos on the performance of 8 and 10 core Xeons when multithreading is accounted for in apps that support it and then get back to me. There is reasoning to do things...

In hindsight this is why people still use Mac Pro's in 5,1 and 6,1 configuration. But then this iMac was always a stop gap and I didn't feel like having to buy a monitor and all the rest of the crap involved.

In the ebay link above, the seller offer free shipping... Australia is not a far far away country I suppose. Unless you insist on buying your parts locally.

Regarding the 8 core and 10 cores Xeon, I already said in my previous post.
8/10 cores Xeon => LGA 2011 will not fit to the LGA 1150 socket on the logic board of iMac 2013 you own. Go read something about it from Intel web page then keep dreaming....
 

rin67630

macrumors 6502a
Apr 24, 2022
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371
4. It comes with a 512gb internal SSD. Although it has a NVME port, has anyone had any luck installing Open Core with Ventura or Sonoma on an NVME drive instead?
Yes, me. I use to break the fusion drive when the SSD is 121 GB, install macOS and the apps on the internal NVMe SSD and move the user home folder to the SATA drive.
NVMe is 4 times faster than SATA.

By the way: with that way of running, you even can keep a HDD (formatted hfs+) to hold your user data and avoid having to open the iMac. For most everyday tasks, it will not be noticeably slower than with a SSD.
 
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