After noticing little to no performance difference in P55 native-controller performance with the Asus and Gigabyte boards, we decided to represent the chipset’s SATA and USB 2.0 controllers only once to simplify data charts. Asus and Gigabyte also use the same USB 3.0 controller, although different PCIe implementations require consideration of both. Gigabyte also offers eSATA, which is one of the technologies USB 3.0 is intended to replace, so the performance of its JMB362 eSATA controller is also compared.
Sequential Reads are limited by hard drive performance for all but the USB 2.0 interface in today’s test configuration. A faster drive in the Asus-supplied USB 3.0 kit would have likely improved this situation.
Sequential write tests may prove more revealing. Gigabyte’s implementation of the NEC USB 3.0 controller mimics that of the P55 chipset’s native SATA, while its first-generation PCIe-to-eSATA controller appears limited to around a 125 MB/s peak. Similarly, Asus’ USB 3.0 implementation falls to around 122 MB/s peak. Potential write-speed shortfalls of both third-party controllers are almost hidden by the performance of the 500GB Seagate 7200.12 hard drive.