2019 21.5” iMac - performance issues and upgrade options

[bjornb]

Hi everyone,
Earlier this year I purchased a refurbished 2019 iMac (3.0 ghz 6-core, 16gb RAM, 1TB fusion drive). I knew that the hard drive would be a problem, but I had no idea it would make this Mac nearly unusable (slow, lots of crashes, etc.). Reverting to an older OS helped a bit but it was still really disappointing, especially compared to my 2013 15” MacBook Pro, which still runs incredibly well. Since the iMac is still under warranty (from the seller) I didn’t want to open it up to put in an SSD just yet, so I’ve been booting it from an external SSD, which is a big improvement, but for some reason things still don’t run as smoothly as my MBP.

The warranty runs out in the next few months, so once that happens I’m considering installing an internal SSD and bumping the RAM to 32gb. My question is, is there any reason why the machine should run better from an internal drive rather than a usb-c connected external one? Secondly, does it make sense to double the RAM, or is that overkill? Lastly, what SSD out there would give me the best performance? Any particular models to look for?

Thanks, I’d appreciate any feedback.

Björn

 

[pigoo3]

My question is, is there any reason why the machine should run better from an internal drive rather than a usb-c connected external one?

Yes...internal data path speeds are faster than data transfer speeds of the ports for external devices.

But...I think port speeds have been getting better & better...and couple this with an external SSD...and in many cases running from an external SSD drive can actually be feasible (not too slow).

If you ran your computer with an external "spinner" hard drive (much slower than an external SSD)...you might notice a greater difference in speed compared to the external SSD being used currently.

Also...at the moment you're comparing the speed of an external SSD to an internal Fusion drive (which is basically a fast hard drive)...not the best/most fair comparison.

If you were comparing the speed of an external SSD to an internal SSD...this would be a more fair test.

Secondly, does it make sense to double the RAM, or is that overkill?

Technically speaking...RAM on 2019 21.5" iMac's is not supposed to be upgradeable (original purchaser of the iMac needs to purchase it with as much RAM as it will every need). But...technically upgrading the RAM in 2019 21.5" iMac's is possible...just very very complicated.

Please zoom to the 8:20 in this video to see the RAM:

With 16GB of RAM currently...this is probably plenty for most users. If you do serious photo or video editing...maybe more RAM could help.

Lastly, what SSD out there would give me the best performance? Any particular models to look for?

In case you didn't know...the 2019 21.5" iMac with the Fusion drive is the lowest end model. The reason this is important is...this model is not capable of installing an internal "blade SSD"...your only option is a 2.5" SSD installed in the bay where the fusion drive is currently.

If this 2019 21.5" iMac was a higher model (not base model)...it would have come with a "blade SSD"...and thus you would have been able to upgrade the internal blade SSD.

The problem with the base model 2019 21.5" iMac with the fusion drive is...it does not come with the hardware to install a blade SSD.

As far as what model SSD to install...this may depend on the storage capacity you're looking for & your budget for the internal SSD.

HTH,

Nick

 

[bjornb]

Thanks for the detailed reply. I would like to install at least a 1TB SSD, though I would go with 2TB if I can find an affordable option. I didn't realize that I wouldn't be able to add a blade SSD, that's unfortunate.

I'm an illustrator, so I do edit a lot of large files in Photoshop, and I also do some video editing in After Effects. I thought 16GB of RAM would suffice, but I'm frequently running into situations where the system is lagging, so I do think I would benefit from additional RAM. I've watched a breakdown on how to swap out the RAM, and it's certainly not for beginners, but I've made similar repairs before so that doesn't intimidate me (though maybe it should haha).

 

[pigoo3]

Thanks for the detailed reply. I would like to install at least a 1TB SSD, though I would go with 2TB if I can find an affordable option. I didn't realize that I wouldn't be able to add a blade SSD, that's unfortunate.

An internal SSD installed where the Fusion drive is currently will still be better/faster...but maybe not the ultimate solution if a blade SSD were possible.

I'm an illustrator, so I do edit a lot of large files in Photoshop, and I also do some video editing in After Effects. I thought 16GB of RAM would suffice, but I'm frequently running into situations where the system is lagging, so I do think I would benefit from additional RAM. I've watched a breakdown on how to swap out the RAM, and it's certainly not for beginners, but I've made similar repairs before so that doesn't intimidate me (though maybe it should haha).

You do sound like a good candidate for a RAM upgrade...especially if "time is money"...and this iMac helps you pay the bills! Also especially if you feel like you're experiencing slowdowns currently (could be RAM related, Fusion drive related, or some of both).

Usually the most difficult part of opening these things up...is removing the "glued-in" display glass. Everything else is mostly mechanical connections...just need to be slow and careful disconnecting cables & removing screws.

Nick

 

[bjornb]

According to OWC their Aura Pro x2 is compatible with my iMac model.

Internal Drive Options for iMac (3.00 GHz, Retina 4K, 21.5-inch, 2019)

Easily find compatible Internal Drive Options for iMac (3.00 GHz, Retina 4K, 21.5-inch, 2019).

eshop.macsales.com

If I understand correctly, the fusion drive has a slot for a blade SSD. Has anyone had luck with this approach?