USB 3.0 and SATA 3
Putting the Z77X-UD3H heads up against the Intel DZ77GA-70K in both SAT 3 and USB 3.0 speeds with the same SSD we are able to get a good idea of how there controllers perform. In this case with SATA 3 they are both almost spot on in performance. It was when we tested USB 3.0 that we saw a noticeable difference. With the Z77X-UD3H getting just over 20MB/s less in read speed over USB 3.0. Even with such a difference, the Z77X-UD3H’s USB 3.0 performance is worlds better than USB 2.0. I wouldn’t kick it out of bed for eating cookies, but if USB 3.0 performance is very important to you, there are other options that will give you better performance.