Photos SSD Drive Speed

I have been reading different articles stating that connecting a SSD drive to a Mac via USB 3.0 is not very fast. I have read other articles that contradict that and say it is pretty fast. So, I thought I would do my own testing on my new Photos SSD.


Two Tests

I have two apps that can test hard drive speed. One is a module in the Drive Genius Utility App and the other is an app called DiskMark. I know there are other more professional benchmarking apps out there, but for my home system I thought these would suffice. I should say at the outset, working with the Photos app using my external SSD drive seems faster, but the proof is in the testing.

Drive Genius

When you open Drive Genius you get this screen:

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All you have to do is select the drive you wish to test and then click on the “Speed” module. You will end up with this window:

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Click on Start and Drive Genius tests the “Sequential Read” speed of the drive:

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It rated my read speed at 426 MB/s. That is pretty fast for an external SSD in my opinion. The Crucial SSD I use in this USB drive is rated at about 520 MB/s I think. Keep in mind, this is on my 4 year old Late 2012 iMac. It does have USB 3.0, but I am sure newer Macs would be a little faster.


The DiskMark app is a simple one-horse-band so to speak. It opens this window on bootup:

Diskmark Window

Click on “Select volume to start speed test”, navigate and choose the volume you wish to test and click OK. DiskMark runs more tests than Drive Genius


As you can see the “Sequential Read” was 416 MB/s, about the same as Drive Genius.

Please keep in mind any SSD drive will run faster (optimal speeds) when place in the SATA drive architecture of the Mac. I suppose putting this Crucial drive in a Thunderbolt enclosure would improve the speed a bit as well, but Thunderbolt enclosures are kind of pricey.


As far as I am concerned, any “Sequential Read” speed in the 400’s is good enough. As I stated in my previous article, Photos does run snappier, especially in the editing photos area.