Conclusion
ASRock was the first to respond to our pleas for a front-panel USB 3.0 connector, and it appears its choice was a good one. Though we occasionally saw minute differences between the performance of onboard and front-panel cable headers, the difference went both ways and is likely an indication of motherboard design optimizations.
The P55 Extreme4’s use of PCIe 1.1 pathways caused a more marked loss in performance than we saw by moving the cable from one connector to another, but we view that as an Intel issue. Had Intel wanted its P55 to provide high-speed controller interfaces, it would have included those in its original design.
What wasn’t apparently an issue with Intel was the design of the front-panel pin connector. We were told by engineers of other firms that a pin-style connector wouldn’t be adequate for the data rates of USB 3.0, yet ASRock claims to have picked this one up based on a design proposal from Intel. Backing that claim is the fact that many other motherboard manufacturers are now using the same interface, and this standardization is the chief thing we were looking for at the start of this saga.
As other companies continue to copy this interface, we’d like to thank ASRock for “getting the ball rolling” on an issue that will hopefully help us all as the gradual proliferation of USB 3.0 makes the technology more influential in our component choices.