You will have to open up the case anyway to insert your new cards. I doubt very much that your existing USB sockets are on a card. Much more likely to be built into the motherboard which means you can't upgrade them to 2.0. They will continue to operate 1.1.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.