Worst. iMac. Ever. Actually...

[rexone]

...I'd go so far as to say worst Mac we've owned ever...
A while back we bought new from Apple a late 2015, 27-inch, Retina 5K iMac. (3.2GHz i5, 16GB RAM, AMD Radeon R9) as our new family machine.
Now our first Mac was an LC475 (also know as 'that pizza box Mac...') so we've been through quite few different Macs over the years but I have never encountered one so bad as this machine.
Just insanely slow & laggy. Everything takes forever to happen with spinning beach balls on everything you try to do. Even right-clicking for a drop-down menu can take 5+seconds for it to appear.
I've run all of Apples diagnostics & keep it up-to-date but I'm guessing that this was just a total dog of a model.
First off - anyone else had any experience with this model?
And second... - anyone have any suggestions for further diagnostics or fixes?

 

[AZhappyjack]

...I'd go so far as to say worst Mac we've owned ever...
A while back we bought new from Apple a late 2015, 27-inch, Retina 5K iMac. (3.2GHz i5, 16GB RAM, AMD Radeon R9) as our new family machine.
Now our first Mac was an LC475 (also know as 'that pizza box Mac...') so we've been through quite few different Macs over the years but I have never encountered one so bad as this machine.
Just insanely slow & laggy. Everything takes forever to happen with spinning beach balls on everything you try to do. Even right-clicking for a drop-down menu can take 5+seconds for it to appear.
I've run all of Apples diagnostics & keep it up-to-date but I'm guessing that this was just a total dog of a model.
First off - anyone else had any experience with this model?
And second... - anyone have any suggestions for further diagnostics or fixes?

Interesting. I have the exact same iMac, purchased new in February 2016... and it's been a solid machine for me. I edit video (FCPx) and do photo editing (PhotoShop), as well as MS Office stuff, internet, email and more...

Not sure what to suggest... no issues and only a very rare spinning beach ball...

 

[ruslan120]

Sounds like a slow Fusion Drive.

Have you seen this thread regarding storage upgrades?

 

[willmtaylor]

Why folks always assume 1 dud means every unit produced is also a dud, I’ll never understand.

 

[marioman38]

Totally sounds like IO to me. Bad HDD/Fusion Drive. The system is hanging because it has to wait for the data to transfer from the drive.

 

[nambuccaheadsau]

Day of the Fusion Drive is long gone. Blade Drives are the go.

 

[mikehalloran]

Apple designed the 2015 iMac with a PCIe 3 x4 bus and installed components that didn’t take advantage of the bus speed. And not just a little. An inexpensive upgrade can give this a 3—4x speed increase.

Back up your system. Send both parts of the fusion drive to recycling.

Replace that sloooow tiny AHCI blade with a large, fast NVMe 3 x4 blade such as the 970 EVO, WD Black 3D or Sabrent Rocket 3D (not the 4D — too expensive and performs the same as a 3D in a Mac).

The end result will be a 2015 that’s nearly as fast as an SSD only 2017. The only real difference will be that it has Thunderbolt 2 and not TB3.

 

[rexone]

Interesting. I have the exact same iMac, purchased new in February 2016... and it's been a solid machine for me. I edit video (FCPx) and do photo editing (PhotoShop), as well as MS Office stuff, internet, email and more...

Not sure what to suggest... no issues and only a very rare spinning beach ball...

Yeah, okay, that speaks volumes. Example - FCPx is virtually unusable on this machine as it's so laggy, feels like it is just grinding away while it tries to do anything.
[doublepost=1565520923][/doublepost]

Apple designed the 2015 iMac with a PCIe 3 x4 bus and installed components that didn’t take advantage of the bus speed. And not just a little. An inexpensive upgrade can give this a 3—4x speed increase.

Back up your system. Send both parts of the fusion drive to recycling.

Replace that sloooow tiny AHCI blade with a large, fast NVMe 3 x4 blade such as the 970 EVO, WD Black 3D or Sabrent Rocket 3D (not the 4D — too expensive and performs the same as a 3D in a Mac).

The end result will be a 2015 that’s nearly as fast as an SSD only 2017. The only real difference will be that it has Thunderbolt 2 and not TB3.

Thanks Mike. How easy are they to swap-out?
I've cracked open iMacs before & know they can be tricky.

 

[joema2]

...Everything takes forever to happen with spinning beach balls on everything you try to do. Even right-clicking for a drop-down menu can take 5+seconds for it to appear...I've run all of Apples diagnostics & keep it up-to-date but I'm guessing that this was just a total dog of a model... Example - FCPx is virtually unusable on this machine as it's so laggy, feels like it is just grinding away while it tries to do anything.

I have edited 20 terabyte projects in FCPX using a 2013 iMac 27 with Fusion Drive. Of course the media was on external Thunderbolt storage. I also have a 2015 i7 iMac 27 which I edited the same projects in FCPX. It worked well. My 2015 has SSD but I could detect limited FCPX performance difference between that and the 2013 with Fusion Drive.

If it takes 5 sec for a drop-down menu something is seriously wrong. It's not a "total dog" of a machine -- it is somehow misconfigured or malfunctioning.

End-user Apple diagnostics are very minimal and an error-free pass doesn't mean a "clean bill of health". The Apple Genius Bar has much more extensive overnight and multi-day bench diagnostics which have a better chance of finding a problem.

You could first do a few simple checks of I/O systems, such as Blackmagic Speed Test on all drives. Verify the numbers are roughly within the expected range. Make sure there is plenty of free disk space on all drives. Run Disk Utility First Aid on all drives. To best run this on the system drive you must boot into Recovery Mode (CMD+R): https://support.apple.com/en-us/HT201255

If that runs with no problems then rebuild all Spotlight indexes: https://support.apple.com/en-us/HT201716

If the problem is still happening, create and log in from a new user profile: http://osxdaily.com/2017/07/17/how-create-new-admin-account-mac/

If the problem goes away it is related to your user account. If it still happens it is more likely system-wide. In that case the next best step might be a clean install of macOS. This can be done without disrupting your existing apps.

If that doesn't work the next step is erase the entire machine and do a totally clean install of macOS.

 

[Zen_Arcade]

I have edited 20 terabyte projects in FCPX using a 2013 iMac 27 with Fusion Drive. Of course the media was on external Thunderbolt storage. I also have a 2015 i7 iMac 27 which I edited the same projects in FCPX. It worked well. My 2015 has SSD but I could detect limited FCPX performance difference between that and the 2013 with Fusion Drive.

If it takes 5 sec for a drop-down menu something is seriously wrong. It's not a "total dog" of a machine -- it is somehow misconfigured or malfunctioning.

End-user Apple diagnostics are very minimal and an error-free pass doesn't mean a "clean bill of health". The Apple Genius Bar has much more extensive overnight and multi-day bench diagnostics which have a better chance of finding a problem.

You could first do a few simple checks of I/O systems, such as Blackmagic Speed Test on all drives. Verify the numbers are roughly within the expected range. Make sure there is plenty of free disk space on all drives. Run Disk Utility First Aid on all drives. To best run this on the system drive you must boot into Recovery Mode (CMD+R): https://support.apple.com/en-us/HT201255

If that runs with no problems then rebuild all Spotlight indexes: https://support.apple.com/en-us/HT201716

If the problem is still happening, create and log in from a new user profile: http://osxdaily.com/2017/07/17/how-create-new-admin-account-mac/

If the problem goes away it is related to your user account. If it still happens it is more likely system-wide. In that case the next best step might be a clean install of macOS. This can be done without disrupting your existing apps.

If that doesn't work the next step is erase the entire machine and do a totally clean install of macOS.

That is a wonderfully helpful post!

Thanks for posting it!

 

[jmilan0302]

Thanks Mike. How easy are they to swap-out?
I've cracked open iMacs before & know they can be tricky.

Way easier than the older ones, because there is so much less stuff inside than the old ones, and no seperate glass/LCD to get dust on, but that's also an issue because the screen is glued on and you have to buy adhesive strips specifically for it to put it back on. Also just looked at the iFixit teardown, that thing still uses a 3.5" desktop HDD! You could also replace that and have a lot of storage too, and I also noticed the chipset has no heatsink on it, if there is enough clearance you should stick on on it while you're in there anyway.

 

[mikehalloran]

Yeah, okay, that speaks volumes. Example - FCPx is virtually unusable on this machine as it's so laggy, feels like it is just grinding away while it tries to do anything.
[doublepost=1565520923][/doublepost]

Thanks Mike. How easy are they to swap-out?
I've cracked open iMacs before & know they can be tricky.

Pretty easy. You need a few tools and some tape. The plastic pizza wheel cracks these open with the least effort. OWC has a couple of good kits. If you intend to leave the HHD in there for extra storage (you won’t rebuild the Fusion drive), get this one—more than you need but you can service a lot of Macs with it and it’s only $28

https://www.amazon.com/OWC-General-Servicing-Apple-iMacs/dp/B00JQMPWKQ/ref=sr_1_16?crid=1U30Y6IZIPE4W&keywords=2015+imac+27+ssd+upgrade+kit&qid=1565534927&s=gateway&sprefix=2015+imac+27+ssd+upgrade+kit,aps,247&sr=8-16

If you want to replace the HDD with an SSD — again for more storage — get this kit. Unlike some earlier iMacs, the fan on a 2015 won’t roar to full speed if the sensor is missing but with it, the fan idles about 500 rpm lower. Ignore everyone who tells you you don’t need it.
https://www.amazon.com/OWC-Digital-Thermal-Upgrade-OWCDIYIMACHDD12/dp/B00J42HP9O/ref=sr_1_3?crid=1U30Y6IZIPE4W&keywords=2015+imac+27+ssd+upgrade+kit&qid=1565535856&s=gateway&sprefix=2015+imac+27+ssd+upgrade+kit,aps,247&sr=8-3

You need an NVMe 3 x4 blade. Get one of the fast ones that I mentioned earlier. Don’t use the slow ones such as the Intel 660p or Crucial P1 — those are perfect for MacBook Air and 2013–14 iMacs with the slow 3 x1 bus.

Get this adapter. There are others but this is the one that always works.
https://www.amazon.com/Sintech-Adapter-Upgrade-2013-2016-2013-2015/dp/B07FYY3H5F/ref=sr_1_1?crid=233HP3UC39MGY&keywords=sintech+ngff+m.2+nvme+ssd+adapter+card+upgrade+2013-2015+macbook&qid=1565536678&s=gateway&sprefix=Sintech,aps,206&sr=8-1

Here’s the iFixIt page. Watch the OWC video also. a small cardboard box can be used in place of a $13 specialty wedge — really.
https://www.ifixit.com/Guide/iMac+Intel+27-Inch+Retina+5K+Display+Blade+SSD+Replacement/30537

These drives do not support internet recovery. Build a USB OS installer. Needs to be High Sierra or Mojave. Install the OS after installation then use Migration Assistant to pull everything over from your backup. There’s a big long thread on this. Those who have problems used cloning to install the OS. Don’t. Once installed and running, it will behave as if the drive was installed from the beginning i. e. Upgrades and security updates run normally.

 

[ZipZap]

Wouldn't it be easier to get a Samsung X5 and boot the machine externally. If that works you're done. It could be the Fusion Drive, or the motherboard. I would not open if I could resolve another way.

 

[HDJulie]

Totally sounds like IO to me. Bad HDD/Fusion Drive. The system is hanging because it has to wait for the data to transfer from the drive.

I have a similar problem. Mine is a late 2014 model so I've decided to go ahead & upgrade but I'd like to get the current one fixed. Can I bring it to an Apple store & ask them to replace the drive?

 

[ZipZap]

I traded my 2014 in given it had The dust under the screen defect courtesy of Apple engineering.

 

[mikehalloran]

Wouldn't it be easier to get a Samsung X5 and boot the machine externally. If that works you're done. It could be the Fusion Drive, or the motherboard. I would not open if I could resolve another way.

The OP has a 2015 so the answer is No, that won't work. The X5 needs to be bus powered via a Thunderbolt 3 port.

On a 2017 and later, it is easier but it's a lot more money than doing it right. Around here, the labor runs $75. If you buy the blade on Amazon, you can select to have it professionally installed and have the data transferred for around $100 — still more than the price difference between the raw blade and an X5.

 

[mikehalloran]

I would not open if I could resolve another way.

You post that so often it should be part of your signature.

I traded my 2014 in given it had The dust under the screen defect courtesy of Apple engineering.

Which has nothing to do with the subject at hand.

I have a similar problem. Mine is a late 2014 model so I've decided to go ahead & upgrade but I'd like to get the current one fixed. Can I bring it to an Apple store & ask them to replace the drive?

Probably not. Apple is required to be able to service their products for 3 years. This is 5 years old.

An SSD in place of the HDD is a multifold improvement. An NVMe 3 x4 blade, likewise, is a vast improvement over the very slow AHCI that Apple used. The inexpensive Intel 660p is too slow for a 2015 but is perfect for a 2013–14 iMac. You need to run High Sierra or newer.

 

[ruslan120]

I think ZipZap makes a good point. The iMac is designed such that dust accumulates, causing degraded performance over time due to thermals.

Sadly that applies to all iMacs not just this year/make. :-(

 

[Salaryman Ryan]

I have quite a lot of iMacs for my business. I usually go to a third party shop that I trust to get my older iMac's internals dusted off. Keeps my iMacs running in good condition. My oldest Mac is an old white 20 inch 2006 model, that our staff still use for emails and word processing.

 

[throAU]

A while back we bought new from Apple a late 2015, 27-inch, Retina 5K iMac. (3.2GHz i5, 16GB RAM, AMD Radeon R9) as our new family machine.

No SSD i am guessing.

It is crazy that Apple have been selling machines with spinning rust in them, as premium machines for the past 5+ years.

 

[mcpix]

I have 2 of the late 2015 iMacs with 2TB fusion drives and they're both running great. However, when AppleCare runs out next year, I'll probably crack them open and upgrade to an SSD.

 

[CE3]

I think ZipZap makes a good point. The iMac is designed such that dust accumulates, causing degraded performance over time due to thermals.

Sadly that applies to all iMacs not just this year/make. :-(

A little regular dusting + putting a dust cover over your iMac when it's not being used (you can find them on Amazon) should greatly minimize the potential for this problem. I don't think dust is a performance issue for *most iMacs* during the first 3-5 years. But if I still have my iMac in year 4 or 5, my warranty will be used up and I won't be concerned about opening it up to blow the dust out and do some other upgrades if needed.

 

[mikehalloran]

No SSD i am guessing.

It is crazy that Apple have been selling machines with spinning rust in them, as premium machines for the past 5+ years.

I couldn't agree more. Even my parents want their iMacs to be fast.

The 27" all have the PCIe socket on the motherboard even the HDD only version.

The 21.5" are supposed to have that socket only if originally equipped with a Fusion or SSD. Cracking one open often reveals and empty PCIe, however. So, while a SATA III SSD is a nice upgrade for the HDD only version, if you find that socket, throw an NVMe 3 x4 blade inside. Slow 660p or P1 for the 2013–14; fast 970EVO or similar for 2015 and later.

 

[nambuccaheadsau]

As Mike H advises, make OS bootable on a thumb drive of +8GB using DiskMaker X or whatever. Far more reliable for Recovery etc.

 

[Ledgem]

I'm also still using my Late 2015 27" iMac, purchased in late 2015. My internal hardware is upgraded over what the OP is using but I agree with others, it sounds like the Fusion drive is responsible for the slowdowns. It's usually the culprit these days. Real shame that Apple keeps selling those configurations, although I guess it's better than a pure HDD.

Wouldn't it be easier to get a Samsung X5 and boot the machine externally. If that works you're done. It could be the Fusion Drive, or the motherboard. I would not open if I could resolve another way.

Agreed, but as was stated before, the problem is that this iMac only uses Thunderbolt 2. If a drive like the X5 had its own power supply then you could use the Thunderbolt 2 to Thunderbolt 3 dongle that Apple sells, but the X5 (and others like it, from what I've seen) all rely on the Thunderbolt 3 port for their power source. It's a nice design decision but unfortunately the Thunderbolt 2 to 3 adapter does not pass power, so you can't use those drives with the system.

There are separate Thunderbolt 2 enclosures that you can still buy, but despite being outdated, they've maintained their price pretty well. While Thunderbolt 2 cables can now be had at half (or less) their new cost on places like eBay, many of those Thunderbolt 2 peripherals are still expensive... perhaps because of their relative rarity. I'd love to buy one at firesale prices for my own system, but I refuse to spend a few hundred dollars on an outdated peripheral. I'd rather put it into a whole system upgrade.