Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Status
The first post of this thread is a WikiPost and can be edited by anyone with the appropiate permissions. Your edits will be public.
Here is my original installation post:
https://forums.macrumors.com/thread...s.2162435/page-16?post=28414771#post-28414771

Attempt #1: Post upgrade, I cloned my macOS using SuperDuper to the Evo Plus in a USB-C NVME enclosure. I then opened the iMac and swapped the drives. When I powered up, it booted to macOS successfully. However the fusion drive is split and I get an error when I try to run the bootcamp assistant to get my windows partition setup again.

Attempt #2: Re-build Fusion drive with the two SSDs. I’m able to get the 1.5TB fusion drive set up using terminal commands. Bootcamp assistant is still cranky and gives me an error stating it can’t partition the drives. When I run it from the terminal, I get the message that there isn’t enough free space, yet there is more than a terabyte of free space.

Attempt #3: Remove the SATA SSD from the iMac, put it into an enclosure, create an external Windows 10 SSD drive. I followed a guide to attempt this. When I get to the step to plug in the external and pass it through to the VM, Windows 10 makes a bunch of connecting/disconnecting sounds, but the drive is never visible in Disk Manager to manipulate the partitions and install Win 10 on there.

Attempt #4: Re-install 1TB SATA SSD inside the iMac. Format 500gb FAT32, 500GB hfs+. Using VMware with Win 10 on Mac, create a bootable USB drive with windows 10 iso using Rufus. Copy the Bootcamp drivers using Bootcamp Assistant to the USB stick. Reboot, boot to the USB stick, install windows 10. Windows didn't like any of the partitions I made, so I removed them all in the windows installer and let it create 500gb of partitions it liked. Install bootcamp drivers. No sound through the headphone jack or internal iMac speakers. But using my USB speakers, sound is working fine. Brightness control and volume on keyboard does not work. Maybe I'll find a way to get those going, but for now, this works fine. I had to use Paragon Disk Manager to reformat the 500gb space for the Mac, for some reason Disk Utility wasn't able to.

Thanks for your help and all your excellent info.

My user account is 400GB (big downloads).

Screenshot 2022-12-30 at 4.33.36 PM.png






Sorry it's been a long time since I installed the drives and messed with MacOS. I'm not using bootcamp anymore. I sort of forget what I did. I'm kind of thinking about re-installing MacOS. Start fresh.
 
Here is my original installation post:
https://forums.macrumors.com/thread...s.2162435/page-16?post=28414771#post-28414771



Thanks for your help and all your excellent info.

My user account is 400GB (big downloads).

View attachment 2134847





Sorry it's been a long time since I installed the drives and messed with MacOS. I'm not using bootcamp anymore. I sort of forget what I did. I'm kind of thinking about re-installing MacOS.
Start afresh.
A very good idea.I cannot pretend to be an expert, however there are a few points which I this forum demonstrates are essential. Ref discussions MikeHalloran, Dobrink, Mboss, MBerhr2 and rxs0

1.
Split Fusion Drive into individual drives before upgrading. Aim to keep them separate as Fusion created with 2 SSD’s is high risk error. In fact there is a persuasive argument for critical backup to be preserved on HDD according to Enterprise Storage Forum:

‘However, some real-life tests allow us to draw reasonable conclusions. In 2016, Google and University of Toronto reported the results of a joint 4-year study that tracked SSD and HDD reliability in Google’s data-intensive data centers.The study demonstrated that the age of the SSD was the main factor in drive failures. They also reported that Google replaced SSD drives about a quarter less often than HDDs. However, SSDs reported more errors than the HDDs, with more bad blocks and uncorrectable errors’.
P.S. SSD failure happens suddenly without warning. HDD failure is usually preceded by noises or odd behaviour so there is better warning.

2. Do not pre-load o/s on NVME. Install NVME clean and format when installed as part of Recovery o/s installation

3. Absolutely do not clone system Big Sur and above as Apples system is now proprietory. To quote Mike Bombich: ‘Copying Apple's system is now an Apple-proprietary endeavor; we can only offer "best effort" support for making an external bootable device on macOS Big Sur (and later OSes).

4. Create your o/s via Recovery.

5. Import your account files from TM backup in preference to Migration Assistant. That is an Apple opinion. ‘Why’ was not explained.

6. For Samsung Driver, use Samsung Iso installed via terminal see:

Sorry, cannot help with Windows at all.

I plan on using 2TB NVMe and retaining 2TB HHD as a second backup disk for Archive material. External T7 SSD holds TM automatic backup.
I shall quote results when completed.
 
Last edited:
  • Like
Reactions: hifitoaster
1) I backed everything up with Time Machine to an external HD.

2) Create bootable USB Ventura installer

3) My 970 EVO Plus has firmware 2B2QEXM7. I noticed there is a 4B2QEXM7 firmware on Samsung's site. I also noticed updated firmware for my 870 EVO "SVT02B6Q for Mac".

I created bootable USB drives and attempted to update them while installed in the iMac. I tried various methods (Etcher, dd, unetbootin) and different USB flash drives but the updater would just hang and not boot into the update OS (stuck at a black screen with a square white cursor).

So I disassembled the iMac, removed the drives, installed them in my PC. I was able to update the 870 but the 970 EVO Plus kept saying there was no drive matching to update. After many attempts, I searched online and found out that the 4B2QEXM7 firmware is targeting only certain specific drive serial numbers.

Since my 970 Evo Plus 2B2QEXM7 firmware was already MacOS compatible (I updated it when I installed it in 2020), I figured I'm done messing with firmware.

4) I put the iMac back together and installed Ventura 13.1 from a bootable USB drive I'd prepared.

5) When MacOS was done installing and at the setup portion, I selected to restore using Time Machine. That process took a few hours. After addressing some AppleID stuff and security permissions that needed to be addressed, I'm back up and running.

- Before Reinstall -
Boot time: 5min 22sec
Blackmagic Disk Speed Test: 556 MB/s write, 1279 MB/s read.

- After Reinstall -
Boot time: 22sec
Blackmagic Disk Speed Test: 2690 MB/s write, 2778 MB/s read.

Thanks for all the help!
 
Happy New Year begins with iMac strip-down!
Glad to learn you can save 5mins every time you start-up. 22 secs is good for 400GB.

Reading your comments, I think I was too imprecise in my item 2 recommendation. Perhaps my omissions made the process more difficult.

As I have no access to a PC I am particularly concerned to avoid Samsung Magician and .exe files which makes Terminal very attractive.

I envisaged you put clean NVMe in place, close up the imac then use Terminal to locate and install the Samsung.iso. I note 4B2QEXM7 is the only firmware.iso for EVO plus. 2B2QEXM7 is not listed on current site. The significance of 4B vs 2B may relate to Elpis or Phoenix controller.

• Does your Evo Plus NVMe use the Phoenix controller or the Elpis?

I get the impression you worked on Windows PC with Unetbootin to update driver on USB on a PC.
I created bootable USB drives and attempted to update them while installed in the iMac. I tried various methods (Etcher, dd, unetbootin) and different USB flash drives but the updater would just hang and not boot into the update OS (stuck at a black screen with a square white cursor).
• What was the updater?

• Glad you got back into operation and found the exercise successful.

Best Wishes,
Tony
NOTE: This thread seems to describe your issue: https://forums.macrumors.com/thread...plus-firmware-upgrade-problem-solved.2220069/
 
Last edited:
- Before Reinstall -
Boot time: 5min 22sec
Blackmagic Disk Speed Test: 556 MB/s write, 1279 MB/s read.

- After Reinstall -
Boot time: 22sec
Blackmagic Disk Speed Test: 2690 MB/s write, 2778 MB/s read.
5 Minute Boot Time for any SSD is to long and i am sure it relates to the known Samsung Trim Problem while booting:

To check the time Trim is consuming on Boot enter in Terminal:
Code:
log show --predicate "processID == 0" | grep spaceman
 
• Does your Evo Plus NVMe use the Phoenix controller or the Elpis?

I get the impression you worked on Windows PC with Unetbootin to update driver on USB on a PC.

• What was the updater?

Based on this reddit post and looking at my 970 EVO Plus part number, I believe I have the Phoenix controller. I don't want to open the iMac and remove the drive and label to verify this :) I also think the date of Jan 2020 also indicates the earlier Phoenix controller.

IMG_2057.jpeg



I used Etcher and dd on MacOS and Unetbootin on Windows 10. All of those had the exact same result. No drive detected that the Samsung bootable USB ISO would update. I think this is ok, it's an earlier version of the 970 EVO Plus and the new firmware isn't needed nor is compatible with that drive.

The other thing I'm pleased about is the alignment of my Thunderbolt/USB/Ethernet ports is now perfectly aligned. I've opened this iMac a few times for a few upgrades over time. The previous time I didn't verify port alignment by plugging in Thunderbolt/USB/Ethernet cables while the system board wasn't screwed down. So the thunderbolt ports weren't quite right. I could use them but the cables would be at an angle. The iFixit guide points out this as something to watch out for. Anyway, all is well now! I just have to remember to make a cut out for the mic when reinstalling the adhesive strips!
 
Based on this reddit post and looking at my 970 EVO Plus part number, I believe I have the Phoenix controller. I don't want to open the iMac and remove the drive and label to verify this :) I also think the date of Jan 2020 also indicates the earlier Phoenix controller.

View attachment 2135593


I used Etcher and dd on MacOS and Unetbootin on Windows 10. All of those had the exact same result. No drive detected that the Samsung bootable USB ISO would update. I think this is ok, it's an earlier version of the 970 EVO Plus and the new firmware isn't needed nor is compatible with that drive.

The other thing I'm pleased about is the alignment of my Thunderbolt/USB/Ethernet ports is now perfectly aligned. I've opened this iMac a few times for a few upgrades over time. The previous time I didn't verify port alignment by plugging in Thunderbolt/USB/Ethernet cables while the system board wasn't screwed down. So the thunderbolt ports weren't quite right. I could use them but the cables would be at an angle. The iFixit guide points out this as something to watch out for. Anyway, all is well now! I just have to remember to make a cut out for the mic when reinstalling the adhesive strips!
 
Steep learning curve with Samsung currently. Yes Hifitoaster, I had read the ‘Toms Hardware’ and Reddit posts previously.
The ISO code you cite indicates your EVO has Phoenix controller. I think this is better than Elpis. Although Elpis has a 4x bigger cache, as you have read, transfers larger than 115GB drop to 800mbps while Phoenix with the smaller cache of 42GB drops to a more effective 1500GB/s, thus giving a more consistent standard of performance. Let us hope your TRIM issue does not recur.

Happily Genexx gives us a simple solution to reset TRIM with Terminal.
Thank You Genexx for the Terminal trim code check. very useful indeed.

Thank you for all the information guys,

Cheers,
Terra Australis
 
Installed today the WD Black 770. Everything went fine.

First thing what took my attention: while the iMac was still opened, I tried to reinstall a new copy from Ventura coming from a USB installer I previously made on this iMac.

After pushing the button "install new OS", it took barely 12 mins to complete this install... Crazy.

From now on it's wait and see. Computer runs very fast, but at first with the Samsung SSD I had the same behavior.
Read & Write speeds are around 3000MB/s. Almost the same result as with Samsung.

To comment on your early questions:
I disabled TRIM once before with no succes. Did a reinstall with TRIM disabled, gets slow again.
Now I let everything standard.
Probably after the fist OS upgrade I will know more. Definitely sure around Summer.
 
  • Like
Reactions: hifitoaster
As i have no experience with the 770 Model, the WD Series NVME seem to work fine Trim related and also Energy Protocol related in many OSX Installations.

I have the WD SN850 and no Problems with the SN750 these are the best choices, maybe we can add the new 770 as well.

In the Hackintosh Scene it is well known that many Samsung NVME are making Problems.
 
All this talk of Samsung issues makes me tempted to grab a WD NVME and install that instead. I haven't yet buttoned up the iMac here. I see a sale price on the 1TB WD 770 for $91 at a local store. I was hoping the fresh install of MacOS rather than the clone would solve the issues for good, but perhaps not.
 
It takes time for Trim to become an issue related to writing Data on the SSD.
After a while some People got 20min Boot Time with some Samsung.
Also Macbook User experiencing short Battery Times.

I know from the Crucial P5 that it constantly uses 9W on OSX while the WD SN850 is using all relevant Energy States.

I guess you made a good decision.
Cloning or fresh Install makes no difference if there is no misconfig on the System.
 
Local Best Buy sales at the moment:

SN770 500GB - $51
SN570 1TB - $74
SN770 1TB - $92
SN850 1TB - $146

You mentioned SN850, what about the other WD models? Do they seem ok for MacOS?
 
I have only experience with the SN850 and got it for a low Price.
The SN 750 is also known to work perfekt.
You may better ask the Hackintosh Community.
 
  • Like
Reactions: hifitoaster
Installed today the WD Black 770. Everything went fine.

First thing what took my attention: while the iMac was still opened, I tried to reinstall a new copy from Ventura coming from a USB installer I previously made on this iMac.

After pushing the button "install new OS", it took barely 12 mins to complete this install... Crazy.

From now on it's wait and see. Computer runs very fast, but at first with the Samsung SSD I had the same behavior.
Read & Write speeds are around 3000MB/s. Almost the same result as with Samsung.

To comment on your early questions:
I disabled TRIM once before with no succes. Did a reinstall with TRIM disabled, gets slow again.
Now I let everything standard.
Probably after the fist OS upgrade I will know more. Definitely sure around Summer.
Good News Indeed!
Great speed results. From reading I understand a significant factor will be operating temperatures. Feedback is mixed but reviews comment that WD Black runs hot. Heat sink recommended and Fan adjustment valuable. Some have made similar remarks about Samsung, both can hit 80°C. Difference appears to be more Samsung installations are not properly operating on Mac as this blog shows. So that may explain why some Samsung users are operating at 35° to 55°C and others up to 80°C. Of course the work load has a much to do with it. As I use Adobe Creative suite without video my workload is light by comparison with other users who have vast throughput.
Regarding TRIM, my comment about switching off had more to do with testing at start-up. TRIM OFF slows the NVMe NAND operation considerably. Operating system runs TRIM to help NAND work more efficiently and faster. So TRIM should always be ON.
All this talk of Samsung issues makes me tempted to grab a WD NVME and install that instead. I haven't yet buttoned up the iMac here. I see a sale price on the 1TB WD 770 for $91 at a local store. I was hoping the fresh install of MacOS rather than the clone would solve the issues for good, but perhaps not.
Why buy PCIe 4.0 for a computer limited to PCIe 3.0? Just bargain hunting?
Price of Samsung EVO Plus at considerable discount that makes it very attractive if you take care with installation. 2TB @ $159.99 Amazon.
Apple firmware has now been updated so EVO PLUS should not be a TRIM problem if installed properly. Most, but not all posts complaining about EVO Plus and TRIM predate Apple firmware upgrade. I suspect cloning the o/s may create the TRIM problem for post firmware upgrade.
I would welcome feedback on that opinion.
Fresh o/s install,
essential as I mentioned earlier, (ref Mike Bombich) cloning no longer reliable for Big Sur and above:
 

Attachments

  • Screen Shot 2023-01-03 at 7.35.12 am.jpg
    Screen Shot 2023-01-03 at 7.35.12 am.jpg
    461.1 KB · Views: 101
Last edited:
Boot time seems to be increasing again :( I'm at about 60 seconds to boot now. I was booting in 22 seconds. Also my write speed tests have dropped quite a bit. I've messed with toggling TRIM off and on with trimforce.

Hmm maybe it's time for a WD drive...

Screenshot 2023-01-02 at 3.43.31 PM.png
 
Very sorry to learn that after all the time you spent. I can understand the attraction of buying a WD Black. However other members have successfully used Samsung EVO Plus without TRIM or Sleep or other problems so the installation process must surely be the culprit. I assume you have disconnected Fusion and are setting up individual drives?

Your speed test it appears slow with writes. They should be closer to 2500 MB/s. Reads are not too bad for PCIe 3.0. I would expect over 3000 MB/s

Re-reading your procedure, the part that I find odd is the inability for you to format NVMe via iMac.

‘I tried various methods (Etcher, dd, unetbootin) and different USB flash drives but the updater would just hang and not boot into the update OS (stuck at a black screen with a square white cursor)’.

1. After fitting NVMe, I assume you booted iMac into Recovery, selected Install Ventura, Agreed to Apple terms then selected NVME drive? Did the o/s recognise the NVME drive? you selected it and the screen changed to install process with the progress bar visible and an installation time estimate?

I can confirm the installer sits with the process bar not moving as the mac is doing pre installation checks and formatting the drive. Perhaps you mistake this for hanging? The stated time estimate may move 1 minute after waiting five minutes or more. It is very slow. Then the installation does take place in fits and starts. I make a cup of Tea! All this is with standard Apple NVME and Fusion Drive. Nothing to do with Samsung.

2. I suspect that if you do not install this way there is a high risk inherent errors.

3. Another thought; prior to further experiment run Command D for a firmware test and Command /Option P+R to check NVRA/PRAM to confirm your iMac is clean.

4. I sent the you tube video of the Terminal NVMe driver installation method which is entirely an Apple o/s secure operation. My logic was that if the Apple o/s does all the work of driver recognition and the installation of everything, the result should be successful. Introducing other applications or cloning etc seem to invite dysfunction. Perhaps try the Terminal method with clean NVMe?

Footnote: Prior to further experiment run Command D for a firmware test and Command /Option P+R to check NVRA/PRAM to confirm your iMac is absolutely OK.

Hope this helps.
Cheers,
 
Last edited:
Good News Indeed!
Great speed results. From reading I understand a significant factor will be operating temperatures. Feedback is mixed but reviews comment that WD Black runs hot. Heat sink recommended and Fan adjustment valuable. Some have made similar remarks about Samsung, both can hit 80°C. Difference appears to be more Samsung installations are not properly operating on Mac as this blog shows. So that may explain why some Samsung users are operating at 35° to 55°C and others up to 80°C. Of course the work load has a much to do with it. As I use Adobe Creative suite without video my workload is light by comparison with other users who have vast throughput.
Regarding TRIM, my comment about switching off had more to do with testing at start-up. TRIM OFF slows the NVMe NAND operation considerably. Operating system runs TRIM to help NAND work more efficiently and faster. So TRIM should always be ON.

Why buy PCIe 4.0 for a computer limited to PCIe 3.0? Just bargain hunting?
Price of Samsung EVO Plus at considerable discount that makes it very attractive if you take care with installation. 2TB @ $159.99 Amazon.
Apple firmware has now been updated so EVO PLUS should not be a TRIM problem if installed properly. Most, but not all posts complaining about EVO Plus and TRIM predate Apple firmware upgrade. I suspect cloning the o/s may create the TRIM problem for post firmware upgrade.
I would welcome feedback on that opinion.
Fresh o/s install,
essential as I mentioned earlier, (ref Mike Bombich) cloning no longer reliable for Big Sur and above:
It seems to be a religious matter to use a Samsung NVME.

When the WD SN850 was on offer ( 99 for 1TB ), I just grabbed it regardless of the PCIe standard and it is no problem to operate at PCIe3 with 3000MB/sec, especially since the NVME then also works cooler.

Beside the fact i was knowing it works Perfect and could not get a SN750 also do not want to spend Time with troubleshooting and earn Money while working instead.

The Crucial P5 worked very good before but also costs 12sec at Boot Time and did not use the Power States of MAC OS. The Power Consumption so was the only reason for me to change. It was not slowing down.
Also used the Crucial P2 in several MacMini 2014 Upgrades with no Problems. Cause i never used any Samsung NVME or SSD on Mac ever i have no Data except the user experience of many many other with Problems known.

Personally I only know that in a Hackintosh the Samsung PM991 which is often used in HP PC or also Lenovo etc., also as second HD parallel operation immediately leads to a kernel panic.
Installation not Possible.

Everybody can decide.

btw. cloning is no problem for me also with Ventura ( was even in beta Phase ) if your Installation is not shredded from useless software tools, regardless of Mike Bombich´s comment, which he had to make cause the Process now relies on Apple APFS.
There was a case in this Forum when ESET Anti Virus Mac was the cause of Replication to fail.

And the cloning Process vs. fresh Install never changed anything related to the Samsung Trim Problem with OSX.
I have worked on hundreds of Cases/Threads with this Problem.

"If APFS replication fails repeatedly​

Apple's APFS replicator will fail if there are problems with your installation of macOS, filesystem corruption on the source, storage driver conflicts, problems with the hardware, or if there are any media read failures. In short, it's just not very tolerable of real-world conditions. CCC's file copier is battle-tested — we've built years of experience into it to handle all sorts of challenging conditions with grace. In cases where Apple's APFS replicator simply can't get the job done, we recommend that you use CCC's file copier to make a backup of your Mac's Data volume."

OpenCore Guide:

Storage

Storage is a section that can be quite confusing as there a lot of mixed reports regarding PCIe/NVMe based devices, many of these reports are based off old information from back when PCIe/NVMe drives were not natively supported like block size mattering or require kexts/.efi drivers. Well, High Sierra brought native support for these types of drives but certain ones still do not work and can cause instability if not removed/blocked out at an ACPI level.

The other big issue surrounds all Samsung NVMe drives, specifically that they're known to slow down macOS, not play well with TRIM and even create instability at times. This is due to the Phoenix controller found on Samsung drives that macOS isn't too fond of, much preferring the Phison controller found in Sabrent Rocket drives and Western Digital's in-house controllers(WD SN750). The easiest way to see this is with boot up, most systems running Samsung drives will have extra long boot times and have their drives run hotter due to the software TRIM failing(hardware TRIM still should be enabled but no partiality). Also some older Intel drives and Kingston NVMe drives also experience these issues.

And while not an issue anymore, do note that all of Apple's PCIe drives are 4K sector-based so for best support only choose drives with such sectors.


Note for laptop users: Intel SSDs don't always play nicely with laptops and can cause issues, avoid when possible

SSD/Storage Options that are NOT supported:

  • Any eMMC based storage (commonly found in netbooks, some tablets and low end computer models.)
  • Samsung PM981 and PM991(commonly found in OEM systems like laptops)
  • Micron 2200S
    • Many users have report boot issues with this drive
  • SK Hynix PC711
    • The proprietary Hynix NVMe controller on this drive is not supported at all, and it will not boot with macOS
SSDs to avoid

Samsung:

Intel:

For all NVMe SSDs, its recommended to use NVMeFix.kext (opens new window)to fix power and energy consumption on these drives
 
Last edited:
I installed a 1TB WD SN770 last night. Boot time is now 13 seconds. Speed tests are nice and fast. I read too much info about samsung nvme issues and wanted a different drive. Even after 1 day of use it was already slowing down, maybe it was worn out after 2 years of use and it's buggered up TRIM implementation. https://github.com/acidanthera/OpenCorePkg/blob/0.6.8/Docs/Configuration.tex#L2592-L2632

Oh I also noticed significantly lower temperatures on the new WD. I was noticing 60c, 65c on the Samsung 970 EVO Plus. This WD runs at 36c.

Anyway.... we'll see how things go from here. :)

Screenshot 2023-01-02 at 10.17.27 PM.png
 
  • Like
Reactions: genexx
It seems to be a religious matter to use a Samsung NVME.

When the WD SN850 was on offer ( 99 for 1TB ), I just grabbed it regardless of the PCIe standard and it is no problem to operate at PCIe3 with 3000MB/sec, especially since the NVME then also works cooler.

Beside the fact i was knowing it works Perfect and could not get a SN750 also do not want to spend Time with troubleshooting and earn Money while working instead.

The Crucial P5 worked very good before but also costs 12sec at Boot Time and did not use the Power States of MAC OS. The Power Consumption so was the only reason for me to change. It was not slowing down.
Also used the Crucial P2 in several MacMini 2014 Upgrades with no Problems. Cause i never used any Samsung NVME or SSD on Mac ever i have no Data except the user experience of many many other with Problems known.

Personally I only know that in a Hackintosh the Samsung PM991 which is often used in HP PC or also Lenovo etc., also as second HD parallel operation immediately leads to a kernel panic.
Installation not Possible.

Everybody can decide.

btw. cloning is no problem for me also with Ventura ( was even in beta Phase ) if your Installation is not shredded from useless software tools, regardless of Mike Bombich´s comment, which he had to make cause the Process now relies on Apple APFS.
There was a case in this Forum when ESET Anti Virus Mac was the cause of Replication to fail.

And the cloning Process vs. fresh Install never changed anything related to the Samsung Trim Problem with OSX.
I have worked on hundreds of Cases/Threads with this Problem.

"If APFS replication fails repeatedly​

Apple's APFS replicator will fail if there are problems with your installation of macOS, filesystem corruption on the source, storage driver conflicts, problems with the hardware, or if there are any media read failures. In short, it's just not very tolerable of real-world conditions. CCC's file copier is battle-tested — we've built years of experience into it to handle all sorts of challenging conditions with grace. In cases where Apple's APFS replicator simply can't get the job done, we recommend that you use CCC's file copier to make a backup of your Mac's Data volume."

OpenCore Guide:

Storage

Storage is a section that can be quite confusing as there a lot of mixed reports regarding PCIe/NVMe based devices, many of these reports are based off old information from back when PCIe/NVMe drives were not natively supported like block size mattering or require kexts/.efi drivers. Well, High Sierra brought native support for these types of drives but certain ones still do not work and can cause instability if not removed/blocked out at an ACPI level.

The other big issue surrounds all Samsung NVMe drives, specifically that they're known to slow down macOS, not play well with TRIM and even create instability at times. This is due to the Phoenix controller found on Samsung drives that macOS isn't too fond of, much preferring the Phison controller found in Sabrent Rocket drives and Western Digital's in-house controllers(WD SN750). The easiest way to see this is with boot up, most systems running Samsung drives will have extra long boot times and have their drives run hotter due to the software TRIM failing(hardware TRIM still should be enabled but no partiality). Also some older Intel drives and Kingston NVMe drives also experience these issues.

And while not an issue anymore, do note that all of Apple's PCIe drives are 4K sector-based so for best support only choose drives with such sectors.


Note for laptop users: Intel SSDs don't always play nicely with laptops and can cause issues, avoid when possible

SSD/Storage Options that are NOT supported:

  • Any eMMC based storage (commonly found in netbooks, some tablets and low end computer models.)
  • Samsung PM981 and PM991(commonly found in OEM systems like laptops)
  • Micron 2200S
    • Many users have report boot issues with this drive
  • SK Hynix PC711
    • The proprietary Hynix NVMe controller on this drive is not supported at all, and it will not boot with macOS
SSDs to avoid

Samsung:

Intel:

For all NVMe SSDs, its recommended to use NVMeFix.kext (opens new window)to fix power and energy consumption on these drives
Thank you for a valuable contribution Genexx.
Not a religious issue for me with Samsung, I am an orthodox Fink; just trying to resolve why Samsung works for some but not others. I can quite appreciate that frustration ultimate leads one to toss the question aside - quit tinkering, buy a more compatible alternative and get on with life.

Hifitoaster has the EVO Plus. Maybe a different installation method will get it to work. Maybe he will buy a WD Black and find that is the easiest way out.
were I in his position I would hate to waste a good product due to a glitch.

You make a number of useful observations which I appreciate Genexx.

One difficulty with this post is that those who have successfully updated 19.1 iMacs have not followed up with performance feedback over time. If the Phoenix controller or whatever, is not fully compatible, surely a majority, if not all users would find TRIM issues extending boot time. We lack full information.

Your reference to APFS and NVMe Fix are most valuable. I accept many helpful observations you have offered. Regrettably, I am unconvinced about your faith in cloning for Apple o/s post Big Sur. Like you, I have used CCC for decades and it has been unfailingly reliable. Now Apple APFS has become essential, I get the impression any cloning involving Apple o/s is potentially risky. Mike Halloran has a similar view and says he never clones an o/s. The fact that making bootable external drives from CCC clones is open to risk indicates the sensitivity of the new (post Big Sur) Apple o/s. It may be as you say,
it's just not very tolerable of real-world conditions.
but that is all the more reason to use Apple approved tools and methods only. Recommending CCC for data is very different from using CCC for o/s. I have tried making an APFS external Monterey bootable drive using with CCC. The system operate fine with some Apple features or behaviors missing. While I have made a totally reliable external bootable drives for Big Sur and Monterey on a Samsung T7, with Recovery and have all Apple operational features. But that is a discussion for another time.

Meanwhile, Hifitoaster has a nice new WD Black and I hope he is very happy.

Thanks again for the input.
 
Last edited:
  • Like
Reactions: genexx
I installed a 1TB WD SN770 last night. Boot time is now 13 seconds. Speed tests are nice and fast. I read too much info about samsung nvme issues and wanted a different drive. Even after 1 day of use it was already slowing down, maybe it was worn out after 2 years of use and it's buggered up TRIM implementation. https://github.com/acidanthera/OpenCorePkg/blob/0.6.8/Docs/Configuration.tex#L2592-L2632

Oh I also noticed significantly lower temperatures on the new WD. I was noticing 60c, 65c on the Samsung 970 EVO Plus. This WD runs at 36c.

Anyway.... we'll see how things go from here. :)

View attachment 2136529
Hi Hifitoaster,

Speeds look excellent and I am sure you are happy to put the tinkering behind you.

Best Wishes,
 
  • Like
Reactions: hifitoaster
Installed today the WD Black 770. Everything went fine.

First thing what took my attention: while the iMac was still opened, I tried to reinstall a new copy from Ventura coming from a USB installer I previously made on this iMac.

After pushing the button "install new OS", it took barely 12 mins to complete this install... Crazy.

From now on it's wait and see. Computer runs very fast, but at first with the Samsung SSD I had the same behavior.
Read & Write speeds are around 3000MB/s. Almost the same result as with Samsung.

To comment on your early questions:
I disabled TRIM once before with no succes. Did a reinstall with TRIM disabled, gets slow again.
Now I let everything standard.
Probably after the fist OS upgrade I will know more. Definitely sure around Summer.
Thanks for your input Jefke.
Enjoy the speed. Let us know how you go for operating temperature. As a Gen 4 running at Gen speeds temperature should be moderate.
Cheers,
 
Crazy... I did exactly the same upgrade in February. I used the same Blade SSD as KrazyKanuck, in the same iMac.
But... after the first OS upgrade my computer started to slow down in booting.
After first install, he booted an empty Monterey in 15 secs. Two months ago, it took almost 3 mins.

Firstly, I hoped Ventura will solve the problem, so I upgraded to Ventura (at night, don't have any idea about the upgrading time). Still, +3 mins boottime.
Next, I made a TimeMachine backup, format the Samsung blade and reinstalled Ventura and my backup.
Boottime was about 25-30 secs.
After the upgrade to Ventura 13.1, he slows down till almost 1 min. So this 970 Evo Plus will be removed as soon as possible.

I already saw some very positive experiences with WD Black blades. They seems to be cheaper compared with last year, so I will order such drive.
I forgot to ask, does your Evo Plus carry Phoenix or Elpis Controller?
Put another way, which model number do you have?
Cheers
 
Here's my upgrade story, feel free to add to the post:

ATTEMPT #1: FAIL

Device: 2017 iMac 18.3 27" Retina 5K
CPU upgrade: 3.5Ghz i5-7600 -> 4.2GHz i7-7700
Blade upgrade: Samsung 970 EVO Plus Series - 2Tb
HDD upgrade: 1TB SATA HDD -> Seagate 16TB HDD Exos X16
Temperature sensor: none
Heatsink: 10mm Aluminum m2 Heatsinks
Speed test: 1500 MB/s read, 1500 MB/s write
Adapter: NONAME (shortie) 2050C5
Issues after fresh OS install: It worked for a few days, then started crashing with minutes after boot and not finding the start disk on start. The heatsink was too tall ad pushed the drive into the back panel. The short adapter obviously did not provide PCI3.0x4.


ATTEMPT #2: SUCCESS

Device: 2017 iMac 18.3 27" Retina 5K
CPU upgrade: 3.5Ghz i5-7600 -> 4.2GHz i7-7700
Blade upgrade: WD_BLACK 2TB SN770 - Gen4
HDD upgrade: 1TB SATA HDD -> Seagate 16TB HDD Exos X16
Temperature sensor: none
Heatsink: Heat Sink Copper for 2280 M2 SSD
Speed test: 3000 MB/s read, 2700 MB/s write
Adapter: ELIATER 2135C5
Issues after fresh OS install: NONE, NVMe Temp remains in 30–38 °C range at all times.


When I took my iMac apart, I figured that the drive has been upgraded by the previous owner, for it had WD_BLACK SN750 500GB and a short adapter. But I had plans to upgrade i5 with i7 anyways (really love those 8 logical cores), as well as 1 TB HDD with quite fast 16 TB HDD (250MB/s read/write which is half an SSD speed), and 500 GB NVMe with 2 TB and PCIe3.0x4 speed.

CPU upgrade was actually the simplest thing of all, just plug and play (and boy i7 is hot ~41 °C nominal temp, but I can live with it). I had multiple issues with the NVMe upgrade, though:
1. The 10 mm tall heat sink I used was a) too tall, so it was pushing int the back panel and b) it had a bottom panel that made the drive too thick and damaged my 1st adapter when I tried to screw it (torn the connector).
2. The adapter didn't have a longer screw, so I had to use the original one, which was barely long enough.
3. And of course this ***** Evo 970 PLUS: somebody claimed it worked for them, so it did for me (only with the short adapter though) but after a few days the system just started crashing every 5–10 min (sleep was disabled) and failing to start without powering off. The drive was falling off even in Recovery mode as I was cloning it to WD.

But finally everything works and works at full speed. I created a second APFS partition that has 500 GB of NVMe as master and 16 TB HDD as secondary, following this guide, so essentially it works as a Fusion drive for data storage (at ~2700 MB/s as well!). The remaining 1.5 TB NVMe used as system and cache disk. Of course, since data is on the fusion drive, I had to also add an external Time Machine.

FinalCut and Lightroom are quite happy, but I no longer have coffee time while they render.
 
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
Here's my upgrade story, feel free to add to the post:

ATTEMPT #1: FAIL

Device: 2017 iMac 18.3 27" Retina 5K
CPU upgrade: 3.5Ghz i5-7600 -> 4.2GHz i7-7700
Blade upgrade: Samsung 970 EVO Plus Series - 2Tb
HDD upgrade: 1TB SATA HDD -> Seagate 16TB HDD Exos X16
Temperature sensor: none
Heatsink: 10mm Aluminum m2 Heatsinks
Speed test: 1500 MB/s read, 1500 MB/s write
Adapter: NONAME (shortie) 2050C5
Issues after fresh OS install: It worked for a few days, then started crashing with minutes after boot and not finding the start disk on start. The heatsink was too tall ad pushed the drive into the back panel. The short adapter obviously did not provide PCI3.0x4.


ATTEMPT #2: SUCCESS

Device: 2017 iMac 18.3 27" Retina 5K
CPU upgrade: 3.5Ghz i5-7600 -> 4.2GHz i7-7700
Blade upgrade: WD_BLACK 2TB SN770 - Gen4
HDD upgrade: 1TB SATA HDD -> Seagate 16TB HDD Exos X16
Temperature sensor: none
Heatsink: Heat Sink Copper for 2280 M2 SSD
Speed test: 3000 MB/s read, 2700 MB/s write
Adapter: ELIATER 2135C5
Issues after fresh OS install: NONE, NVMe Temp remains in 30–38 °C range at all times.


When I took my iMac apart, I figured that the drive has been upgraded by the previous owner, for it had WD_BLACK SN750 500GB and a short adapter. But I had plans to upgrade i5 with i7 anyways (really love those 8 logical cores), as well as 1 TB HDD with quite fast 16 TB HDD (250MB/s read/write which is half an SSD speed), and 500 GB NVMe with 2 TB and PCIe3.0x4 speed.

CPU upgrade was actually the simplest thing of all, just plug and play (and boy i7 is hot ~41 °C nominal temp, but I can live with it). I had multiple issues with the NVMe upgrade, though:
1. The 10 mm tall heat sink I used was a) too tall, so it was pushing int the back panel and b) it had a bottom panel that made the drive too thick and damaged my 1st adapter when I tried to screw it (torn the connector).
2. The adapter didn't have a longer screw, so I had to use the original one, which was barely long enough.
3. And of course this ***** Evo 970 PLUS: somebody claimed it worked for them, so it did for me (only with the short adapter though) but after a few days the system just started crashing every 5–10 min (sleep was disabled) and failing to start without powering off. The drive was falling off even in Recovery mode as I was cloning it to WD.

But finally everything works and works at full speed. I created a second APFS partition that has 500 GB of NVMe as master and 16 TB HDD as secondary, following this guide, so essentially it works as a Fusion drive for data storage (at ~2700 MB/s as well!). The remaining 1.5 TB NVMe used as system and cache disk. Of course, since data is on the fusion drive, I had to also add an external Time Machine.

FinalCut and Lightroom are quite happy, but I no longer have coffee time while they render.

Here's my upgrade story, feel free to add to the post:

ATTEMPT #1: FAIL

Device: 2017 iMac 18.3 27" Retina 5K
CPU upgrade: 3.5Ghz i5-7600 -> 4.2GHz i7-7700
Blade upgrade: Samsung 970 EVO Plus Series - 2Tb
HDD upgrade: 1TB SATA HDD -> Seagate 16TB HDD Exos X16
Temperature sensor: none
Heatsink: 10mm Aluminum m2 Heatsinks
Speed test: 1500 MB/s read, 1500 MB/s write
Adapter: NONAME (shortie) 2050C5
Issues after fresh OS install: It worked for a few days, then started crashing with minutes after boot and not finding the start disk on start. The heatsink was too tall ad pushed the drive into the back panel. The short adapter obviously did not provide PCI3.0x4.


ATTEMPT #2: SUCCESS

Device: 2017 iMac 18.3 27" Retina 5K
CPU upgrade: 3.5Ghz i5-7600 -> 4.2GHz i7-7700
Blade upgrade: WD_BLACK 2TB SN770 - Gen4
HDD upgrade: 1TB SATA HDD -> Seagate 16TB HDD Exos X16
Temperature sensor: none
Heatsink: Heat Sink Copper for 2280 M2 SSD
Speed test: 3000 MB/s read, 2700 MB/s write
Adapter: ELIATER 2135C5
Issues after fresh OS install: NONE, NVMe Temp remains in 30–38 °C range at all times.


When I took my iMac apart, I figured that the drive has been upgraded by the previous owner, for it had WD_BLACK SN750 500GB and a short adapter. But I had plans to upgrade i5 with i7 anyways (really love those 8 logical cores), as well as 1 TB HDD with quite fast 16 TB HDD (250MB/s read/write which is half an SSD speed), and 500 GB NVMe with 2 TB and PCIe3.0x4 speed.

CPU upgrade was actually the simplest thing of all, just plug and play (and boy i7 is hot ~41 °C nominal temp, but I can live with it). I had multiple issues with the NVMe upgrade, though:
1. The 10 mm tall heat sink I used was a) too tall, so it was pushing int the back panel and b) it had a bottom panel that made the drive too thick and damaged my 1st adapter when I tried to screw it (torn the connector).
2. The adapter didn't have a longer screw, so I had to use the original one, which was barely long enough.
3. And of course this ***** Evo 970 PLUS: somebody claimed it worked for them, so it did for me (only with the short adapter though) but after a few days the system just started crashing every 5–10 min (sleep was disabled) and failing to start without powering off. The drive was falling off even in Recovery mode as I was cloning it to WD.

But finally everything works and works at full speed. I created a second APFS partition that has 500 GB of NVMe as master and 16 TB HDD as secondary, following this guide, so essentially it works as a Fusion drive for data storage (at ~2700 MB/s as well!). The remaining 1.5 TB NVMe used as system and cache disk. Of course, since data is on the fusion drive, I had to also add an external Time Machine.

FinalCut and Lightroom are quite happy, but I no longer have coffee time while they render.
 
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.