It's really quite hard to sum things up. We spent a week testing all the host controllers and we spent even more time sourcing the hardware we've used for this test, yet we've come out disappointed after weeks of hard work. Why you ask? Well, for one none of the host controllers reached the kind of performance numbers we expected, especially as the host controller makers have been showing benchmarks in excess of 300MB/s, reaching as high as 400MB/s in the case of Fresco Logic. We did our best to bypass system bottlenecks and we made sure we used the latest drivers available to us.
We're also disappointed by all the little compatibility issues and although the blame for this is ultimately with the hardware manufacturers, it feels like if the USB-IF had been a stronger force and had steered up things from day one a little bit better, maybe, just maybe we wouldn't have these issues today. For one, the fact that we're having two different xHCI standards in shipping products where older xHCI 0.96 compliant controllers lack certain features which are holding back power saving support on external storage devices is a poor show of a standard.
Then there are issues like UASP where license fees are involved. This is just plain dumb and it's ultimately holding back a lot of the advantages that USB 3.0 can offer. The UASP protocol is vastly superior to BOT (Bulk Only Transfer) and not only does it allow for a performance increase, but it can also help prevent data loss and it allows for sensible handling of multiple file transfers at once.
Our intent with this test was simple; we wanted to find out which companies made the best USB 3.0 host controllers. At the end of the day, there's no real clear winner, although ASMedia, Etron and Renesas seems to offer somewhat better performing solutions than the competition. We were utterly disappointed with the performance of AMD's integrated USB 3.0 host controller, as it really didn't offer the kind of performance we expected to see. We can only hope that the USB 3.0 chip makers are willing to start to co-operate better in the future so that we can see improved interoperability between various USB 3.0 devices, as the way things are at the moment, USB 3.0 isn't going to win over a lot of fans.