Western Digital My Passport User Manual page 29

Q: Why is the data transfer rate slow?
A: Your system may be operating at USB 1.1 speeds due to an incorrect driver
installation of the USB 3.0 or USB 2.0 adapter card or a system that does not
support USB 3.0 or USB 2.0.
Q: How do I determine whether or not my system supports USB 3.0 or USB 2.0?
A: Refer to your USB card documentation or contact your USB card manufacturer.
Note: If your USB 3.0 or USB 2.0 controller is built in to the system
motherboard, be sure to install the appropriate chipset support for your
motherboard. Refer to your motherboard or system manual for more
information.
Q: What happens when a USB 3.0 or USB 2.0 device is plugged into a USB 1.1 port or
hub?
A: USB 3.0 and USB 2.0 are backward-compatible with USB 1.1. When connected to a
USB 1.1 port or hub, a USB 3.0 or USB 2.0 device operates at the USB 1.1 full speed
of up to 12 Mbps.
If your system includes a PCI Express slot, you can achieve USB transfer rates by
installing a PCI Express adapter card. Contact the card manufacturer for installation
procedures and more information.
MY PASSPORT FOR MAC
USER MANUAL
TROUBLESHOOTING – 25