Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

pbedrosi

macrumors newbie
Original poster
Mar 10, 2015
26
2
Nashville
i'm about to open my Late 2012 iMac 27" to replace the fusion HD with a single 1TB blade SSD (w/Adapter). I will be ditching the mechanical drive and will not replace it with anything. I intend the pull the SATA cable out as well.

Any issues with this plan? does the iMac need a physical drive attached to SATA cable?
 
My advice is to go ahead and replace the SSD portion of the fusion drive with the blade SSD.

BUT...
There's no need to remove the platter-based hard drive.
Just reformat it and use it for extra storage or perhaps as a bootable backup (in case the blade SSD ever fails).

Two drives are ALWAYS better than just one.
 
  • Like
Reactions: ignatius345
Good points while I go through the trouble of opening up the machine. I'm not doing any heavy computing on this machine so I was trying to simplify the "mechanicals" considering the eventual failure of the platter drive this being a 2012 machine. I was just worried if the iMac would freak out without a physical drive.

So I think I may just throw in a Crucial 2.5" 128Gb SSD I have laying around (adapter coming). Thanks for the input.
 
Your 2012 model probably wont be able to take the advantage of any modern NVME blade Flash Storage, so I would not bother with higher complexity of replacement and instead, stick with a regular SSD in place of HDD and call it a day.

I had 2012 model and had Samsung 850 Pro and had no issue and the performance was day and night compared to spinning HDD, but mine was HDD only, not Fusion.
 
  • Like
Reactions: Nguyen Duc Hieu
i'm about to open my Late 2012 iMac 27" to replace the fusion HD with a single 1TB blade SSD (w/Adapter). I will be ditching the mechanical drive and will not replace it with anything. I intend the pull the SATA cable out as well.

Any issues with this plan? does the iMac need a physical drive attached to SATA cable?

Check the compatibility issue of SSD blade.
Mainly there are 2 types:
SATA SSD
nVME SSD
Each type goes with a different adapter.
 
Last edited:
Any issues with this plan? does the iMac need a physical drive attached to SATA cable?
While many left some useful advice, I don't think anyone answered your actual question.

AFAIK, the OEM HDDs still have an internal temp sensor that if the HDD is pulled or swapped with something other than an Apple OEM drive, then the OS will make the fans run on full blast.

This can be avoided many different ways. The two most common is adding a SATA connector with an external temp sensor on it, or using SW to control the fan speed, such as Macsfancontrol.

Personally, I would just use the SATA temp sensor adapter, it isn't that expensive.

There are other ways as well, such as jumping/shorting the two leads for the temp sensor, or wiring your own temp sensor.

I intend the pull the SATA cable out as well.
Well, this limits what you can do, but you can still potentially short the leads on the other side of the SATA cable, or just use a SW solution.

i'm about to open my Late 2012 iMac 27" to replace the fusion HD with a single 1TB blade SSD (w/Adapter).
As others has mentioned, there isn't any advantage of using a faster SSD to replace the blade SSD on the Late 2012 iMacs. They will only run at 6Gbps.

I won't stay that there is not reason to do it, because if you already had the parts sitting around and wanted to use them, I guess that could be a reason, but there will not be any performance advantages to doing it.

The fastest non-RAID drive setup possible on the Late 2012 iMac is using an external NVMe over Thunderbolt 3.

If you really wanted to keep everything internal, you could also do a RAID0 setup with the internal blade SSD (or SSD with adapter) and replacing the HDD with a SATA SSD. This would be faster than the external TB3 drive.
 
first off, thanks guys. I've spent a bit of time last night (a lot) and got the upgrade done.

Everything is working well except for the fan as Juicy Box said. I Have the screen being held by painters tape until I decide to seal it up. Honestly, not interested in spending another $35 on OWC temp control sensor, so I may short the SATA cable or ditch it since its only connected to a spare 128gb SSD.

Here is what I used to upgrade...which included a new WiFi/BT card from 2013 iMac and new termal paste on GPU/CPU.

IMG_4015.jpeg
IMG_4016.jpeg
IMG_4017.jpeg
IMG_4018.jpeg
IMG_4019.jpeg


Here is the original Wifi/BT Card...
IMG_4023.jpeg


The updated 2013 version....wifi speeds way up, and unlock with Apple Watch now works....it was a pain however to re-install new OS, had to borrow PC wired keyboard and mouse during install.
IMG_4022.jpeg


The blade M2 SATA SSD fit perfectly...Speed test over Fusion improved, but not a bid deal..Write speeds went from ~250Mb/s to ~400Mb/s, read speeds slightly less improved.

IMG_4024.jpeg
IMG_4025.jpeg


One of the other reasons to open up the iMac was to clean it out.....this is not even the worst of it.

IMG_4021.jpeg


General tip for those opening up the iMac and having some difficulty with adhesive strips...after pulling off the factory adhesive strips there will be residue left behind....this needs to come off to get proper adhesion. Between goo-be-gone and rubbing alcohol it will come off.

IMG_4020.jpeg


Now I need to see how to short this SATA cable....
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.