Hi Tiggmeister,
No LED pilot lights suggests a fault with the power unit. Then you say everything is working and you are getting good NVMe speed. So what was the cause of the problem and how did you fix it?
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A list of successful iMac 27" (2012-2019) SSD upgrades
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No LED pilot lights suggests a fault with the power unit. Then you say everything is working and you are getting good NVMe speed. So what was the cause of the problem and how did you fix it?
How Old? - place this comment in context.
I have not found EFI a problem as EFI is automatically updated with each Apple o/s - or even more recent than that with Apple updates within an o/s series. Download and use free Silent Knight to check EFI update on your iMac.
I can imagine a mismatch between choice of new NVME on an older o/s or vice versa for that matter. However my PCIE 3.0 2019 iMac had no EFI problem with recent PCIE 4.0 NVME Samsung or WD Black drives running Ventura. They were instantly recognised.
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Yes, I will post those numbers you mentioned once I have all my parts for the upgrade. I went with a PCIE 4 for the same reason you mentioned. I considered the SN 770. However, since I was able to get the SN 850x for the same price, I went with the faster one. I probably won't be able to run it at full speech because of the limitation of my iMac 27" 5K core i9 2019 (iMac 19,1), but I can convert it to a nice external drive in the future. Looking forward to working on the upgrade soon.
I can tell you exactly. 2015 and older imacs do NOT have firmware for an nvme placed on the motherboard socket. They may have updated firmware but it did not include the code for this type of ssd. Whereas, the mac pro 5,1 firmware WAS updated to include this even though the ssd has to be fitted onto a pcie card. So these older imacs will probably work anyways but there is a known wake from sleep issue. Whereas, the 2017 and 2019 imacs can handle the nvme ssds ....
Thank you for that explanation. That fits with information supplied by Dobrink on Page 1 of this Topic.
When deciding on the heatsink make sure it's not thicker than 3mm - otherwise you might force it into the case and bend it. Below is a comparison shot with the 5mm (left) and the 3mm heatsink (right) in a 2019 iMac. The left is not a pretty sight.
Best,
Magnus
This is contrary to my own experience - even a 2013 iMac works fine with NVMe SSDs. But there was an issue with getting the respective firmware installed (one needed to get the original Apple SSD disconnected first?), perhaps anybody knows the details?
With the heatsink, it seems that the WD Black SN850x comes to a thickness of close to 9mm. I guess I won't be using a heatsink, at least not the one that comes with the original SSD. Thank you for the advice. The photos are especially helpful.
Regards,
Stephen
That's well known. Initially, when on High Sierra, that was a real problem (I experienced it myself). Later, with firmware updates (e.g. coming with Mojave) you'd notice successful conversions without the issue.
If thats true then you would need to update the guide on page 1 of this thread. Still, personally I do not think its worth the effort to update the mobo ssd on older imacs.
Please excuse me for being a bit off the main topic of this forum, but I wanted to get some advice on upgrading a 2017 21.5" iMac 18,1. Has anyone had any experience upgrading the HDD to SSD on this iMac? I'm thinking about upgrading it to SSD 2tb. Do you need a combo cable with a temperature sensor for this upgrade? Or, can you do without it like most of the newer 27" iMacs?
No special cable, a 2.5in sata ssd fits straight in there and gives a 4x speed increase. I use crucial ones
Blade upgrade by @MacNB2
Device: Late 2013 - 14,2 - ME089LL (3.4Ghz i5-4670, 1TB HDD, No Blade).
Blade added: 1TB Kioxia EXCERIA G2 PCIe/NVMe 1.3 Gen3x4
HDD upgrade: 1TB SATA HDD -> -/-
BootROM version: 433.140.2.0.0
SMC Version: 2.15f7
Speed test: ~660 MB/s read, ~770 MB/s write
OS: Catalina 10.15.7
Adapter: eBay
Heatsink: eBay
Temperature sensor: not used - not needed for NVMe
Issues after Cloning HDD->SSD: NONE, no sleep or hibernate issues
This iMac model did not include an Apple blade so the socket was empty.
Kept the existing HDD spinner as a backup drive (that's also bootable).
All has been working fine for last six months.
Until a couple of week ago....while using it the iMac, the screen just went black and rebooted into the HDD (not the SSD).
This booted fine. But could not see the NVMe SSD in Finder nor Disk Utility...the NVMe SSD just disappeared
Shutdown.
Pulled the Power plug and waited 1 minute. Pressed the Power Button for 30 sec to ensure no residue power.
Plugged Power cable in and waited 30 secs.
Powered up and kept Alt+CMD+P+R for three bongs and released to reset NVRAM.
Pressed Alt key to see the Apple Startup disk picker....but only the HDD spinner listed
Restarted and held the D key on the keyboard to start the internet diagnostics.
Diagnostics found no errors (code AD000).
Restarted and held Alt key to see the Apple Startup picker....hey presto NMVe SSD and HDD listed.
Booted from NVMe fine and thought ...problem solved without knowing what was the problem.
Ran DriveDX App and there are absolutely no issues flagged with the NVMe after 700 hours ON time and ~300 power Ups. Max Temp never exceeded 48 Deg C.
Has been running fine for two weeks....till today...same problem...the screen just went black and rebooted into the HDD (not the NVMe SSD). Arrrrrgh.
Tried everything I did before to make the NMVe "visible" but now not seen at all. IOREG shows no PCIe NVMe Device.
What can cause this ? NVMe or Logicboard failure or both ?
Tempted to dismantle it all and replace the NVMe with a new one but it could be the Logicboard ?
UPDATE:
Had no choice but to dismantle the whole iMac again
First I checked if the NMVe had come off the mount (causing the issue) but it was seemed screwed in perfectly :
![IMG_5365.jpg]( "IMG_5365.jpg")
On removing the Logic board, I noticed that I had inserted the NVMe+Adapter into the connector "too" deep such that some of the pins on the Adapter appear to be shorting with the Logic board connector shield :
![IMG_5361.jpg]( "IMG_5361.jpg")
OOOPS !
Did a bit of search (something I should done before the installation) and came across post here that thoroughly documented how to add an NVMe and pitfalls to be aware of.
Basically, I had to cover the exposed pins with Kapton tape to stop them from touching the connector shield:
![IMG_6370.JPG]( "IMG_6370.JPG")
The NVMe was "seen" and able to boot but it appears the OS or something was corrupted (presumably when it suddenly stopped working). Many Apps would not open and the beachball ruled. Cloning the working HDD to the NVMe solved that issue.
So fingers crossed that this shorting was the only issue and not the NVMe or the Logic board 🤞
Device: Late 2013 - 14,2 - ME089LL (3.4Ghz i5-4670, 1TB HDD, No Blade).
Blade added: 1TB Kioxia EXCERIA G2 PCIe/NVMe 1.3 Gen3x4
HDD upgrade: 1TB SATA HDD -> -/-
BootROM version: 433.140.2.0.0
SMC Version: 2.15f7
Speed test: ~660 MB/s read, ~770 MB/s write
OS: Catalina 10.15.7
Adapter: eBay
Heatsink: eBay
Temperature sensor: not used - not needed for NVMe
Issues after Cloning HDD->SSD: NONE, no sleep or hibernate issues
This iMac model did not include an Apple blade so the socket was empty.
Kept the existing HDD spinner as a backup drive (that's also bootable).
All has been working fine for last six months.
Until a couple of week ago....while using it the iMac, the screen just went black and rebooted into the HDD (not the SSD).
This booted fine. But could not see the NVMe SSD in Finder nor Disk Utility...the NVMe SSD just disappeared
Shutdown.
Pulled the Power plug and waited 1 minute. Pressed the Power Button for 30 sec to ensure no residue power.
Plugged Power cable in and waited 30 secs.
Powered up and kept Alt+CMD+P+R for three bongs and released to reset NVRAM.
Pressed Alt key to see the Apple Startup disk picker....but only the HDD spinner listed
Restarted and held the D key on the keyboard to start the internet diagnostics.
Diagnostics found no errors (code AD000).
Restarted and held Alt key to see the Apple Startup picker....hey presto NMVe SSD and HDD listed.
Booted from NVMe fine and thought ...problem solved without knowing what was the problem.
Ran DriveDX App and there are absolutely no issues flagged with the NVMe after 700 hours ON time and ~300 power Ups. Max Temp never exceeded 48 Deg C.
Has been running fine for two weeks....till today...same problem...the screen just went black and rebooted into the HDD (not the NVMe SSD). Arrrrrgh.
Tried everything I did before to make the NMVe "visible" but now not seen at all. IOREG shows no PCIe NVMe Device.
What can cause this ? NVMe or Logicboard failure or both ?
Tempted to dismantle it all and replace the NVMe with a new one but it could be the Logicboard ?
UPDATE:
Had no choice but to dismantle the whole iMac again
First I checked if the NMVe had come off the mount (causing the issue) but it was seemed screwed in perfectly :
On removing the Logic board, I noticed that I had inserted the NVMe+Adapter into the connector "too" deep such that some of the pins on the Adapter appear to be shorting with the Logic board connector shield
:OOOPS !
Did a bit of search (something I should done before the installation) and came across post here that thoroughly documented how to add an NVMe and pitfalls to be aware of.
Basically, I had to cover the exposed pins with Kapton tape to stop them from touching the connector shield:
The NVMe was "seen" and able to boot but it appears the OS or something was corrupted (presumably when it suddenly stopped working). Many Apps would not open and the beachball ruled. Cloning the working HDD to the NVMe solved that issue.
So fingers crossed that this shorting was the only issue and not the NVMe or the Logic board 🤞
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At march 2023 I upgraded my iMac 2017 (dead Samsung evo970) to new wd sn770 1tb, posted in this thread also. Everything works fine and smooth, have no problems with trim. Now Im running last Big sur version.
Is it safe to go to Ventura? Im curious about motherboard firmware upgrade (if I upgrade to Ventura) and is this possible it can slow down wd black sn770?
Is it safe to go to Ventura? Im curious about motherboard firmware upgrade (if I upgrade to Ventura) and is this possible it can slow down wd black sn770?
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If Big Sur runs OK on you iMac, I do not believe you need any firmware upgrades to run Monterey, Ventura or Sonoma. I am using WD 770 as boot drive on NVME 2019 iMac. EFI is usually updated in Apple updates so as long as you regularly install them you should have no problems. Use ‘SilentKnight’ to confirm EFI is current.
Cheers.
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I have not updated a 2017 iMac specifically for SSD, I have updated 2011 and 2019 iMac with Samsung 870Evo instead of HDD. In both cases I dispensed with temperature control cables as Macs Fan Control software does the job perfectly and reliably. My experience simply replicates what many others in this forum have already confirmed.
For the 2019 iMac both temperature sensor cable as well as Macs Fan Control are not needed. For the 2011 however yes.
Interested in your reference to ‘Yes’ regarding Fan Control for 2011 iMac. As I said I had no problem using Macs Fan Control, what was your experience which demanded a cable?
Probably clearer: for 2011 (and earlier) iMacs you would need either a temperature sensor cable or the Macs Fan Control software.
yes it does, however, the 2019 imac does not need the cable or the software. The 2011 does need one or the other.
iMac HDD Thermal Sensor Bypass - LogiWiki
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