Monterey isn't newer. Until Monday, I was running Ventura with no problems.
I'll have to put the drive inside or remove one of my external monitors which I don't want to do.
Thanks for all the help everybody!
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iMac suddenly unusably slow
- Thread starter jbmillard
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Monterey isn't newer. Until Monday, I was running Ventura with no problems.
I'll have to put the drive inside or remove one of my external monitors which I don't want to do.
Thanks for all the help everybody!
The drive is definitely starting to fail. Please back up anything important immediately. Definitely replace the drive with an SSD when you get a chance. I would not recommend doing it yourself as it's a nightmare if you aren't experienced.
I’ve got the same system (but w/ a new internal 2tb ssd) & noticed some weird slowdowns on mine too in the last few days, so I went back down to Mojave, but it still takes a coupke mins to boot, beachballs occasionally, and I just waited over ten minutes for FCP to start. For such a powerful machine it’s running worse than my pentium 286 did with windows95.
That's a better solution. I wasn't attempting to get you to have 5 external drives hanging from ports on your iMac
I tried the SMC reset. Didn't matter.
I'll try an external hard drive, it would be nice proof that it is the hard drive.
I'll have to see what management wants to do to fix it.
OP wrote:
"I'll probably replace the internal hard drive with an SSD so external will be a moot point."
You understand that a "fusion drive" is actually TWO drives, correct?
- a small blade SSD
and
- a larger platter-based SATA hard drive (HDD).
These two drives are then "fused" together via software so that the user sees only one drive.
It sounds like the HDD portion of the fusion drive is starting to fail (but hasn't failed "completely" yet).
I'm thinking if you replace the internal SATA HDD with a SATA SSD, it would certainly get it running (and speed it up), but I'm wondering if it might actually run FASTER using a USB3.1 gen2 SSD plugged into one of the USBc ports on the back.
A USB3.1 gen2 SSD should give you read speeds in the 850-900MBps range.
Something like the Samsung t7 "Shield" (currently on sale at amazon).
One other thing:
DON'T do anything with the fusion drive (de-fuse, etc.) UNLESS you have a good, current backup.
Once you "split" the drive, all data that was on the drive will be... gone.
"I'll probably replace the internal hard drive with an SSD so external will be a moot point."
You understand that a "fusion drive" is actually TWO drives, correct?
- a small blade SSD
and
- a larger platter-based SATA hard drive (HDD).
These two drives are then "fused" together via software so that the user sees only one drive.
It sounds like the HDD portion of the fusion drive is starting to fail (but hasn't failed "completely" yet).
I'm thinking if you replace the internal SATA HDD with a SATA SSD, it would certainly get it running (and speed it up), but I'm wondering if it might actually run FASTER using a USB3.1 gen2 SSD plugged into one of the USBc ports on the back.
A USB3.1 gen2 SSD should give you read speeds in the 850-900MBps range.
Something like the Samsung t7 "Shield" (currently on sale at amazon).
One other thing:
DON'T do anything with the fusion drive (de-fuse, etc.) UNLESS you have a good, current backup.
Once you "split" the drive, all data that was on the drive will be... gone.
Yes I understand that. Thanks.
My understanding is that I can get an aftermarket SSD and use it to replace the HD, e.g. iFixit kit.
At this point I really don’t want anything connected through the USB C on the back because I’d have to remove one of my external monitors which I really don’t want to do. At least as a permanent solution.
I would just clone the data or whole drive while you can and replace the hd with a large ssd, like a crucial mx500 1,2 4 tb. ignore the apple ssd its not worth getting in there unless you are very keen. and i am not sure the redoing the fusion works with an ssd, so dont bother with that ... all good.
I’d once again recommend if you’re going to pop open the machine, replace the blade ssd. You can do the hard drive too, replace it with a SATA SSD, but if you replace the AHCI drive either with a real apple AHCI ssd, but one of reasonable size, or with an adaptor and a generic NVME, you’ll get all the speed that this generation of iMac can provide. Just replacing the spinner with a SATA ssd will be an improvement, but why not get the most you can out of your machine? An AHCI or NVME drive will run circles around your Fusion Drive even when it was new.
This is exactly what happened to my Fusion Drive. The SSD portion just got worn out while the HDD was actually still OK. I caught it before it failed, but the lesson here was that, as you say, the SSDs on these things were 1) horribly under-spec'ed by Apple and 2) get absolutely hammered with wear as a result of how the Fusion Drive works.
The Fusion Drive was a pretty clever hack when SSDs were still nosebleed expensive, but I think over the next couple years most of the last of them will age out. They have two potential points of failure, so even if the HDDs don't die, the SSDs will absolutely stop working.
In my case, I went got an iFixit kit, cut open the iMac put in a 1TB SATA SSD and called it a day. It was a few hours' careful work and cost me all of $200 including the new SSD.
Great thread on here on exactly this: https://forums.macrumors.com/threads/a-list-of-successful-imac-27-2012-2019-ssd-upgrades.2162435/
I got lazy and cheap (see my post immediately above) and just went the SATA route on mine. It was a 2014 i5 so it was on its way out the door anyway, but that triage let me eke out another year or so until the shiny new M1 iMac came out.
I already have full backups, the last one was done on Sunday. I also have offsite storage. I'm not in danger of losing anything. I have been copying work files to a Windows laptop I have so I can do some work.
I have full backups. I don't trust cloning a drive when it's failing - to me that's a recipe for disaster that may hit months from now when I go to find something.
If you're booting from the 1TB SATA SSD (I assume this means that it replaced the HD) then I would think that the other SSD (on the motherboard) has very little to do (as long as you don't fuse the two). Is that right?
Thanks.
Exactly. I was booting off the SATA SSD and I just reformatted the remaining blade SSD and left it in place. It would show up on the desktop as a little 128 GB drive, but I couldn't trust it with much because, per DriveDX, it was down to <5% of its usable life.
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Awesome. Most people don't even have a single backup solution. I have 4 backups. 3 in a multi-slot backup drive and one off-site drive that goes into a fireproof safe that I update once a month and check for reliability.
If you're asking me, it's not something I would consider. Once hard drives start to fail, I wouldn't trust trying to pull lots of data off of it. If I was looking for a single file and could check it, fine, but I'm not going to try it with large amounts of data.
It's scary, isn't it? This is a work (company owned) computer so backups and off site storage are required. I have backups for all my personal macs too. I keep weekly backups on a removable hard drive in a fire "resistant" safe too.
I've lost things before because of a lack of preparedness and stupidity and I promised myself that would never happen again.
If you don't mind losing a bit of space, i would say that the easiest is to reinstall the SO only on the SSD (and forget the HDs) and just add external capacity for additional storage. It will be also the cheapest I guess, even is not ideal.
It works with an external hard drive, so I don't think it's a circuit board failure. I've ordered a iFixIt kit with a 2TB SSD, we see how that goes.
@jbmillard You might also try a PRAM reset in addition to the SMC. They are two separate subsystems. Sounds like the issue my brother had a few months back and that fixed it.
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You need to be very careful. It’s very easy to crack the screen when you’re putting it back together. Watch as many videos as you can before you do anything.