I have a 4TB MyBook Studio Edition II
It works fine on USB 2.0 and both firewire 800 (on my Mac) and firewire 400 on PC.
I have not been able to get it to work on eSATA at all.
I have tried the onboard sata controller from my motherboard, without success.
I have also tried 2 separate eSATA PCIe controller cards (the first was a Marvell 91xx chipset supporting up to 6Gb/s Sata rev 3), and now a Silicon Image based card. None recognise the unit
Using the same cards, I can happily plug on to a “Hotway ProRaid+” external enclosure, and it is recognised.
I have tried this under Vista 64, and also Win7 64 bit also. Same thing.
I specifically purchased this because of the eSATA speed capability.
I spent $700 (Australian) on this drive, and now have spent hundreds more on different eSATA cables, eSATA cards etc.
There are widespread reports of problems with eSATA on these devices (which I wish I had researched better!) but nothing but silence from WD.
If anyone has managed to get one of these working via eSATA, please let us know what sata controller you have managed to get it working with (or motherboard details) so we can try to narrow down a set of functional controllers.