Terrible Copying Speed Between Two WD Drives

WD External Drives External Drives for Mac
1

I’m copying between two WD MyBooks drives (a 2TB and a 3TB). I reformatted both as Mac OS Extended (Journaled).

I’m using a new Macbook Air, running Mac’s latest OS.

I’m plugging the drives directly into the computer’s USB 3.0 slots (I’m not using a hub).

But I’m only getting 70-90mb/sec speed.

Any suggestions?

2

jimmbo,

What are the specific model numbers of the disk drives involved? Please bear in mind USB 3.0 transfer speeds depend on controller driver support and raw system specs. An average of 70MB/s-90MB/s is within expected performance considering Apple’s implementation of the interface:

http://www.macworld.com/article/2039427/how-fast-is-usb-3-0-really-.html

3

What are the specific model numbers of the disk drives involved?

WDBFJK0020HBK-NESN

and

WDBFJK0030HBK-NESN

considering that 60mb/sec is USB 2.0 speed, I’m shocked that 70-90 would be normal.

4

jimmbo,

Please bear in mind 60MB/s is the maximum sustained output of USB 2.0 on an optimal environment without hardware, bridge (Driver), software (Firmware), or system interference. Most systems peak around 20MB/s.