What OS are you using? Did the PCIE card come with the WD drive? Is this a new computer that came with USB 3.0? There are issues with PC’s built before USB 3.0 was introduced and some cards. Are all of your drivers and BIOS up to date?
I’m using Windows 7 64 bit. this is the card that came with the “My Book”, yes.
The computer is one year old, and doesn’t have usb 3.0 built-in, but i tested the My Book on another brand new computer with usb 3.0 buit-in and it worked fine…