I need to extend my zpool, just need the drives, I noticed that my Supermicro X10SL7-F has additional four SATA II 3.0gbps ports and two SATA III 6.0gbps ports. Will I see any difference when adding 6 new drives if I am mixing the two different speeds 3.0 and 6.0gbps? I will have a total of 12 boards after adding six newer ones most of the are on SATA III 6.0gbps ports. I also need to figure how to fit 6 more in my case :).