My thought on this is..if you have a usb 2 device then by all mean get an usb 2 adapter card. If the usb card can't handle the power that is require by the device then you will also need a hub with external supply also (I think that maybe your problem right now; just guessing).
i have installed an internal dvd rw drive externally using an ide-usb2 adaptor into my pcs' usb1.1 socket.
I get a message saying it wont work due to an I/O problem.Will this be cured by replacing my usb1.1 card with usb2.0

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