Why can my iMac 5k Late 2015 only achieve 700Mb/s read speed?

[macpokerstars]

I have the iMac 5k i5 3.2Ghz Late 2015 and I installed a 256GB PCIe SSD (MZ-JPU256T/0A6).

I can only achieve 700Mb/s read speed instead of 1300, where as my Macbook Pro early 2015 can do 1300Mb/s with its 512GB ssd.

Is it because the model I bought for the iMac is an older SSD? Or is it because of the capacity?

What would happen if I put my Macbook Pro's 512 SSD in my iMac?

 

[Gav2k]

http://barefeats.com/imac5k12.html

I have the iMac 5k i5 3.2Ghz Late 2015 and I installed a 256GB PCIe SSD (MZ-JPU256T/0A6).

I can only achieve 700Mb/s read speed instead of 1300, where as my Macbook Pro early 2015 can do 1300Mb/s with its 512GB ssd.

Is it because the model I bought for the iMac is an older SSD? Or is it because of the capacity?

What would happen if I put my Macbook Pro's 512 SSD in my iMac?

 

[keysofanxiety]

The SSD you installed was from a 2013 rMBP. That's why the speeds are much slower.

Conversely if you installed your 2015 one, you'd see the same speeds you currently are on your rMBP.

TL;DR: speeds are due to the age/model of the SSD.