Need advice with SSD Enclosure as bootable

[got.xid]

Hello,

I own an iMac 2017 5k Retina and want to increase its speed by upgrading the Fusion drive to SSD. I mainly use iMac for photo editing. Heaviest I'd run would be Lightroom classic + Photoshop + Chrome with many tabs at once. Read couple similar posts here, but every single one of em ended up with USB 3.0. Also done some research, but still lot of unsure things such as:

1. How are the temperature of these things when used as bootable drive?
2. Is there good models out there that can handle heavy performance for long period of time?
3. Some specific model apparently freezes your iMac whenever it goes to sleep and you try to wake it up. Is there some glitch I should be concerned about?
4. Is enclosure even necessary? Should I just get it installed in my iMac instead?

The goal is, I want to run a Thunderbolt 3 SSD enclosure and use it as a bootable drive. Looked up couple of models online but no info about how they'll perform if used as bootable; Most were used as backup / storage. I heard it when they perform on heavy tasks, it could become quite hot. Was wondering if anyone can recommend some good set up that's been working for them. Or if there's another solution to speed up my iMac? Should I just buy an SSD and go to local shop with certified Apple technician and ask them to have it install in my iMac?

Thank you in advance!

 

[Nguyen Duc Hieu]

I suppose you Apple Care + policy has expired.
In that case, don't bother with the hassle of opening the iMac and replace them yourself. Leave it to the certified Apple technician if you can afford them.

Request the best Nvme SSD they have, and another SATA 2.5in as well.
Move the current Fusion to an external enclosure, USB 3.0 or Thunderbolt won't make a big difference. The bottleneck is the read/write speed of the spinning drive (top 130~140MB/s)

 

[Fishrrman]

OP wrote:
"The goal is, I want to run a Thunderbolt 3 SSD enclosure and use it as a bootable drive"

Leave the internal fusion drive alone.
It's actually TWO drives -- small blade SSD and larger HDD.

If you want to boot and run via tbolt3 external SSD, just buy one, plug it in, set it up, and start booting from it.

Samsung X5 can do it.
There may be others, but not sure of them.

Possible warning about X5 -- they run HOT. In some cases (under heavy continuous writing), they may get so hot the internal controller "throttles back" the drive to a much slower speed.

They're also expensive.

I'll offer a compromise:
Get a USB3.1 gen2 enclosure, something like this:

ORICO M.2 SATA B+M/B Key SSD Enclosure USB 3.1 Type C 5Gbps External Solid State Enclosure Adapter for 2280/2260/2242/2230 M.2 NGFF SSD 4TB Max, NOT Supoort PCIe NVMe/AHCI M.2 SSD-Black

12 MONTHS FREE REPLACEMENT AND LIFETIME TECHNICAL SUPPORT: If there was any problem with the products from ORICO Direct Store, please contact us, you will get a free-replacement within 12 months.

www.amazon.com

(many others are available, this is just the one I use)

Then, get an nvme "blade SSD" and put it into the enclosure.

This will give you a drive with read speeds around 965MBps, a nice improvement.
Not as fast as tbolt3, but... for most day-to-day uses... you won't "notice the difference".

Less $$$$, too.

 

[got.xid]

OP wrote:
"The goal is, I want to run a Thunderbolt 3 SSD enclosure and use it as a bootable drive"

Leave the internal fusion drive alone.
It's actually TWO drives -- small blade SSD and larger HDD.

If you want to boot and run via tbolt3 external SSD, just buy one, plug it in, set it up, and start booting from it.

Samsung X5 can do it.
There may be others, but not sure of them.

Possible warning about X5 -- they run HOT. In some cases (under heavy continuous writing), they may get so hot the internal controller "throttles back" the drive to a much slower speed.

They're also expensive.

I'll offer a compromise:
Get a USB3.1 gen2 enclosure, something like this:

ORICO M.2 SATA B+M/B Key SSD Enclosure USB 3.1 Type C 5Gbps External Solid State Enclosure Adapter for 2280/2260/2242/2230 M.2 NGFF SSD 4TB Max, NOT Supoort PCIe NVMe/AHCI M.2 SSD-Black

12 MONTHS FREE REPLACEMENT AND LIFETIME TECHNICAL SUPPORT: If there was any problem with the products from ORICO Direct Store, please contact us, you will get a free-replacement within 12 months.

www.amazon.com

(many others are available, this is just the one I use)

Then, get an nvme "blade SSD" and put it into the enclosure.

This will give you a drive with read speeds around 965MBps, a nice improvement.
Not as fast as tbolt3, but... for most day-to-day uses... you won't "notice the difference".

Less $$$$, too.

How is the temperature when used in high performance?

 

[kaans]

DON'T BUY ORICO - AVOID THEM LIKE YOUR LIFE DEPENDS ON IT

You can find some of my experiences with Orico at the bottom of this answer: https://apple.stackexchange.com/a/397169

If you want an SSD Enclosure, get the 10Gbps Asus one, it has a USB-A cable too, it's fast enough, and most importantly, it doesn't do anything funky that makes the SSD hotter than the surface of the sun in 10 seconds - even if you keep it connected for long times, the SSD stays cool