HDD failing, needs to be replaced. I'm not a serious tech guy, but I'm fine with opening the iMac up and installing a replacement SSD. Thinking OWC Mercury Electra 6G (2TB). But should I go instead with an external SSD, maybe a Samsung T7? This would cost a bit less, and the drive would have use when I finally buy a new iMac. Since the computer only has TB2 port, would I need an adapter cable to use this external drive? Which option would provide best performance? What would you do??? Thanks!
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Replacing HDD on 2015 27" iMac
- Thread starter msa62001
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I'd suggest using an external SSD, like the t7.
Then, it will be an easy matter to just unplug the external SSD, take it to the new Mac in the future, and "get migrated" that way.
The t7 is a USB3.1 gen2 drive (NOT a "thunderbolt" drive).
It's still backward-compatible with the USBa ports on the 2015 iMac.
A USB3 (or 3.1 gen2) drive will give you reads in the 420MBps range, with writes around 375MBps (or better).
Also...
I'd suggest Samsung's newer "t7 Shield" drive (instead of the plain-vanilla t7).
Some folks are reporting better performance with the "shield" version.
I have one (first Samsung SSD I've owned), pleased with it.
You didn't tell us which version of the OS you'e using.
When you get the external SSD, REFORMAT IT.
You don't really need the Samsung software that comes on it.
For Mojave and later, format to APFS, GUID partition format.
For High Sierra and earlier, format to Mac OS extended with journaling enabled, GUID partition format.
If the internal HDD is still working at this point, I would recommend using either CarbonCopyCloner or SuperDuper to "clone" the contents of the internal to the SSD.
Both are free to download and use for 30 days.
SD is a little easier to use if you're a first-time user.
Then, it will be an easy matter to just unplug the external SSD, take it to the new Mac in the future, and "get migrated" that way.
The t7 is a USB3.1 gen2 drive (NOT a "thunderbolt" drive).
It's still backward-compatible with the USBa ports on the 2015 iMac.
A USB3 (or 3.1 gen2) drive will give you reads in the 420MBps range, with writes around 375MBps (or better).
Also...
I'd suggest Samsung's newer "t7 Shield" drive (instead of the plain-vanilla t7).
Some folks are reporting better performance with the "shield" version.
I have one (first Samsung SSD I've owned), pleased with it.
You didn't tell us which version of the OS you'e using.
When you get the external SSD, REFORMAT IT.
You don't really need the Samsung software that comes on it.
For Mojave and later, format to APFS, GUID partition format.
For High Sierra and earlier, format to Mac OS extended with journaling enabled, GUID partition format.
If the internal HDD is still working at this point, I would recommend using either CarbonCopyCloner or SuperDuper to "clone" the contents of the internal to the SSD.
Both are free to download and use for 30 days.
SD is a little easier to use if you're a first-time user.
