Thanks for your explanations. Now I've no time to read Paul's last reply and I'll do it later because I want to learn something on that.
~misfit~ solved that with a PCIe so for now I just want to ask you if this https://www.amazon.it/gp/product/B007FVQIVW/ can be good for my scenario. Data transfer is only 3gbps, so it's esata II like my fantec enclosure, but it costs only 5 euros (a bit less than 5 usd) shipped.