I have an Dell Inspiron 560s (low profile, slim—http://support.dell.com/support/edocs/systems/insp560st/en/index.htm) and would like to add a USB 3.0 card Can anyone please advise me as to what I should look for in a such a card? I understand that I need to be careful that it is the right size, since I have a low profile machine in a slim case. It's also been suggested to me that there may be some issue with the power connector, but this was unclear to me. I'm just looking for general guidelines so I don't buy the wrong thing, but, of course, if anyone should have a specific recommendation, I should be grateful. Thanks very much.