So I got a 1.5TB WD My Passport. it is USB 3.0 bus powered. I can't get it to do much besides mount on my 1.1 MacPro. Tried all ports. Works like a charm on my wifes last gen white MacBook (yrs old). Thinking it has to be something to do with lack of proper power from the USB 2.0 ports to power the drive. All for dropping a usb 3.0 PCI card. I see some require SATA power or molex runs. My 2 optical bays are empty and I'm not using my 2 onboard hidden SATA connections either. Any input of best way to go about this, or if it eve is my issue would be much appreciated. Thanks.