As some of you may have noticed, the P67/H67 Express chipsets are the first chipsets from Intel to have a native SATA 6Gbps controller. The previous generation, the 5-series chipsets came only with SATA 3Gbps and any SATA 6Gps ports on those motherboards are from third-party controllers, like Marvell's 88SE9128 SATA 6Gbps controller, which incidentally seems like a popular choice.
During the course of our testing, we soon found that in certain benchmarks - Sysmark 2007 and PCMark Vantage in particular, the results were significantly higher when we were using the Intel P67 SATA 6Gbps controller, compared to the Marvell 9128 controller. As the only variable that changed between our test runs was the SATA 6Gbps controllers, we can reasonably assume that this is the main reason for the discrepancy.
Since the SATA 6Gbps WD Caviar Black 1TB hard drive that we used for all our recent CPU testing has been done with a Marvell 9128 controller, it's possible that when you're comparing the scores of the previous gen Intel Core processors with the new Sandy Bridge ones, like the Core i7-875K for example, the differences between them could be exacerbated by the SATA controller performance. Hence, for all our CPU benchmarks in this review, we have labeled the SATA controller used.
As for the performance discrepancies that we noted, below is an example of the Core i7-2500K on the Intel 6G and the Marvell 6Gbps controllers in some of our benchmarks:
While the results in Cinebench 11.5 was practically identical, there were some slight but significant differences in the other two system suite benchmarks. The Intel controller was around 4% faster in SYSmark 2007 and it grew up to about 15% in PCMark Vantage. While we didn't show the results here, we can tell you that there were no differences in results for the gaming and other rendering benchmarks.
Intel provides only two SATA 6Gbps ports on the P67 chipset, with the board vendor likely to add third-party ones like the Marvell 9128 controller. With these results in mind, we recommend that users opt for the Intel 6Gbps ports when possible, even if the real-world difference may not be obvious.