iM 4,1-14,4 Help: Lack of increased speed when upgrading from SSD to NVME?

[Blueline111]

I expected a greater speed increase when upgrading to an ADATA XPG5X82OO PRO 1TB from Amazon with a Sintech NGFF M.2 SSD adapter.

Former SSD (1TB): 475 MB / 525 MB/s : Read / Write speed.
New NVME (TB): 740 MB / 765 MB/s : Read / Write speed.
ADATA reviews suggest 3,500 MB / 3,000 MB/s: Read / Write speed.

The computer is a late 2013 21.5" iMac with a 3.1GHz Quad-Core Intel i7-4770s and 16GB of RAM. I realized I would not get the top speed as advertised due to the age of the computer but this small speed increase doesn't seem right.

Can anyone shed light why the speed is lacking? Is it the computer? Bad NVME - brand? Blade? Me?

Thanks to anyone and everyone that can solve this mystery.

 

[Bigwaff]

From what I gather, your iMac has PCIe 2.0 x2 so is limited to 1GB/s. So the real question is why aren’t speeds closer to that.

Apple Proprietary SSDs: Ultimate Guide to Specs & Upgrades | BeetsBlog

Apple’s SSDs are confusing. Are they M.2 drives? What connector do they use? AHCI or NVMe? What drive can I use to upgrade? We have answers. We’ll tell which SSDs work in which MacBook Pros, iMacs, Mac minis and more.

beetstech.com

What I find interesting is your numbers are rather in line with SATA 6Gb/s, which your iMac also has.

 

[Blueline111]

From what I gather, your iMac has PCIe 2.0 x2 so is limited to 1GB/s. So the real question is why aren’t speeds closer to that.

Apple Proprietary SSDs: Ultimate Guide to Specs & Upgrades | BeetsBlog

Apple’s SSDs are confusing. Are they M.2 drives? What connector do they use? AHCI or NVMe? What drive can I use to upgrade? We have answers. We’ll tell which SSDs work in which MacBook Pros, iMacs, Mac minis and more.

beetstech.com

What I find interesting is your numbers are rather in line with SATA 6Gb/s, which your iMac also has.

Thanks for you reply. Upon further research I discovered the problem is both the brand and me. Me, because I should have done more research. The Brand, because I found that unfortunately this NVME blade does not like Apple/Mac computers. BTW, late 2013 iMac has PCIe 3x4. Most websites do not mention the issue with Macs.

 

[Bigwaff]

BTW, late 2013 iMac has PCIe 3x4.

I guess the site a referenced has it wrong.