I have an older model WD My Book Essential 320gb external. It's the "green ring" button version. It is a USB 2.0 capable device. It is plugged into a USB 2.0 port on the motherboard (Biostar TA790GX A3+). Operating system is Win7 Business x64. USB 2.0 is properly setup in BIOS.
Other USB 2.0 devices are operating properly at Hi-Speed, but the hard drive will only work at "Full Speed" (USB 1.1). I have tried every port, I have tried different cables, I have uninstalled/reinstalled all USB drivers, and I'm running out of ideas! Transfer speed is quite slow (800-900 kb/s), which is absolutely brutal when trying to transfer large files. A search of the Western Digital knowledge base is unhelpful, as were my google/forum searches. I've found others with similar problems, but no working solutions as of yet.
Any ideas would be greatly appreciated. The idea of waiting 5-6 hours for a few gigs of data to transfer isn't pleasant!