We used a Western Digital WD740GD Raptor to determine storage interface performance. Although this is a Serial ATA 150 device only and a SATA II drive would have returned better interface bandwidth numbers, this usually is quite irrelevant for real world performance. It's the hard drive itself that matters, not the interface.

Access Time

Although the WD Raptor is the quickest desktop hard drive available thanks to its 10,000 RPM spindle, there are some access time differences between each of these south bridge solutions. ULi's interface obviously has the shortest latencies, while ATI, NVIDIA and VIA are slightly slower.

Interface Performance

More differences become obvious here, although it is not ULi dominating the maximum throughput test. NVIDIA's Serial ATA II interface bursts over 130 MB/s across the interface when reading from the Raptor's internal cache memory; at 105 and 112 MB/s, the ATI and ULi parts are clearly behind. Although no hard drive will actually come close to these numbers within the next few months, it is preferable to have a faster interface just in case you decide to upgrade to a faster storage subsystem.