Let's see if we can clear some things up. Apple uses a custom blade SSD in their systems so you really can't use just any SSD that looks similar.
You didn't tell us if you have a HD installed already, so you may need to review your hardware using the 'About This Mac' > System Report to see what you have. If you don't then you'll need to get a cable harness and the rubber boot that supports the drive. At which point you could install a 2.5" SATA SSD.
As for upgrading the current blade drive I would leave your current SSD alone. It's a PCIe 2.0 AHCI 250 GB drive which is ideal as the boot drive & host your apps.
=== Update (11/25/2017) ===
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Karl heres the IFIXIT guide you'll need to follow: [https://www.ifixit.com/Guide/iMac+Intel+21.5-Inch+Retina+4K+Display+Logic+Board+Replacement/64111] as you'll need to get to the back side of the logic board to plug in the SATA cable. Jump down to Step63. Its a bit too tight to do blindly.
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Karl heres the IFIXIT guide you'll need to follow: [guide|64111] as you'll need to get to the back side of the logic board to plug in the SATA cable. Jump down to Step63. Its a bit too tight to do blindly. Make sure you use the correct tools to take the display off as you can damage it quite easily.
Here's the parts you'll need:
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* [https://www.thebookyard.com/product.php?cPath=34_165_458_478&products_id=16056|iMac 21.5" Hard Drive Power & Data Cable - Apple P/N 923-00565]
* [https://www.thebookyard.com/product.php?cPath=34_165_458_478&products_id=16180|iMac 21.5" Hard Drive Cradle Kit - Apple P/N 076-00090]
Let's see if we can clear some things up. Apple uses a custom blade SSD in their systems so you really can't use just any SSD that looks similar.
You didn't tell us if you have a HD installed already, so you may need to review your hardware using the 'About This Mac' > System Report to see what you have. If you don't then you'll need to get a cable harness and the rubber boot that supports the drive. At which point you could install a 2.5" SATA SSD.
As for upgrading the current blade drive I would leave your current SSD alone. It's a PCIe 2.0 AHCI 250 GB drive which is ideal as the boot drive & host your apps.
+
+
=== Update (11/25/2017) ===
+
+
Karl heres the IFIXIT guide you'll need to follow: [https://www.ifixit.com/Guide/iMac+Intel+21.5-Inch+Retina+4K+Display+Logic+Board+Replacement/64111] as you'll need to get to the back side of the logic board to plug in the SATA cable. Jump down to Step63. Its a bit too tight to do blindly.
+
+
Here's the parts you'll need:
+
* [https://www.thebookyard.com/product.php?cPath=34_165_458_478&products_id=16056|iMac 21.5" Hard Drive Power & Data Cable - Apple P/N 923-00565]
+
* [https://www.thebookyard.com/product.php?cPath=34_165_458_478&products_id=16180|iMac 21.5" Hard Drive Cradle Kit - Apple P/N 076-00090]
Let's see if we can clear some things up here. Apple uses a custom blade SSD in their systems so you really can't use just any SSD that looks similar.
+
Let's see if we can clear some things up. Apple uses a custom blade SSD in their systems so you really can't use just any SSD that looks similar.
-
You didn't tell us if you have a HD installed already, so you may need to review your hardware using the About This Mac > System Report to see what you have. If you don't then you'll need to get a cable harness and the rubber boot that supports the drive. At which point you could install a 2.5" SATA SSD.
+
You didn't tell us if you have a HD installed already, so you may need to review your hardware using the 'About This Mac' > System Report to see what you have. If you don't then you'll need to get a cable harness and the rubber boot that supports the drive. At which point you could install a 2.5" SATA SSD.
-
As for upgrading the current blade drive I would leave your current SSD alone here. It's a PCIe 2.0 AHCI 250 GB drive.
+
As for upgrading the current blade drive I would leave your current SSD alone. It's a PCIe 2.0 AHCI 250 GB drive which is ideal as the boot drive & host your apps.
Let's see if we can clear some things up here. Apple uses a custom blade SSD in their systems so you really can't use just any SSD that looks similar.
You didn't tell us if you have a HD installed already, so you may need to review your hardware using the About This Mac > System Report to see what you have. If you don't then you'll need to get a cable harness and the rubber boot that supports the drive. At which point you could install a 2.5" SATA SSD.
As for upgrading the current blade drive I would leave your current SSD alone here. It's a PCIe 2.0 AHCI 250 GB drive.