iMac Hard Drive switch to SSD of 3Gb/s Upgrade

Everyone wants a super fast machine - but back to the basic: by chasing the SSD speed (on paper) would do small part of the "tasks" you intend to.

I have dual boot system on my late 2015 iMac 27" - basic model, like yours. (SATA 1T SSD - 10.15; and PCI-e 256Gb SSD - 10.14)

For 1080P video rendering, music editing and simple photoshop tasks - my SATA SSD provides more then enough.

I even can not tell you the difference between these two SSDs from my day-to-day use.

If you really concern your system, besides hardware (such as SSD), you should look into EtreCheck to take a snap shot of your system. By sharing the EtreCheck result here, many here can provide some insight of any possible issues.

One more word, iMacs are NOT really for users to fiddle around the hardware, inside.

https://eshop.macsales.com/item/OWC/K27IM12HE500/?utm_source=google&utm_medium=shoppingengine&utm_campaign=googlebase&gclsrc=ds

https://www.ifixit.com/Store/Mac/iMac-Intel-27-Inch-Late-2012-Early-2019-SSD-Upgrade-Bundle/IF174-029?o=12

I think those macs have SATA III which is rated at 6Gb/s for the hard drive bay (more like 500MB/s) and a PCIe slot, that is much faster than the SATA III drive channel maybe 4x faster?, for the optional SSD, or Fusion drives which use both.

OWC has both SSD for both available options: 6G SSD 2.5" drives that can fit in the 3.5" drive bay with a mounting bracket rated for SATA III speeds, and they also have the faster flash or blade type SSDs that can fit in the PCIe slot. (some Macs might not have the PCIe slot if a Fusion or SSD was not included when the model was built-to-order, not sure which model years)

https://everymac.com/systems/apple/imac/specs/imac-core-i5-3.2-27-inch-aluminum-retina-5k-late-2015-specs.html

https://eshop.macsales.com/shop/ssd/owc/imac-27-inch/2013-2019

If you have time, you can read the following Apple Propriety SSD

I have the exact same pecs 2015 iMac like yours.

The 1T HDD is SATA-3 (6G) and the back of the logic board (PCI-e) slot can take "PCIe 3.0 x4" Apple propriety SSD - generation 4 per the article indicated.

Speed on SSD - on paper could be different from actual read/write. Your inquiry of 3 Gb/s seems over-reached in real life performance on 2015 27" iMac (SATA-3 could never reach that, nor would PCI-e SSD on late 2015).

oxemanuelexo wrote:

Should I get this one then

https://eshop.macsales.com/shop/ssd/owc/imac-27-inch/2013-2019

I'm not sure which of the two SSDs you are referring since the page lists an Aura X2 PCIe SSD and a standard 2.5" SATA SSD. If you look closely at the footnote for the Aura X2 SSD you will see:

NOTE: Aura Pro X2 is not compatible with iMac17,1 (Late 2015).

Even if the Aura X2 PCIe SSD was compatible it would require you to remove the Logic Board which can be difficult with a lot of risk of being damaged.