Results: Sequential Read And Write Performance
Using AS-SSD to measure sequential read and write performance, Intel's Z77 and Z87 Express platforms, along with AMD's A75 and SB950, are in a dead heat. In the end, Intel's integrated storage controllers wind up slightly ahead. Marvell's discrete controllers on PCIe-based add-in boards fall in behind those four chipsets. Further behind, though, are the AMD SB750, Intel P55 Express, and Intel ICH10R south bridge, taking the last three spots.
The Iometer streaming benchmark confirms what we found in AS-SSD's read component, though a look at sequential writes puts AMD's A75 and SB950 ahead of Intel's mainstream chipsets. Why? In the real world, leaving features like Turbo Boost, SpeedStep, and all of Intel's C-states enabled causes the company's CPUs to switch clock rates constantly. This plays havoc on storage benchmarks that vary host processing loads. We can't be sure that's the cause of our variance, but it's certainly a variable we've seen affect our numbers in the past.
Two Marvell controllers, one on the PCIe board Asus U3S6 (Marvell 88SE9123-NAA2) and the other on MSI's Big Bang motherboard (Marvell 88SE9128-NAA2), come in last. These things are attached via PCI Express x1 links, so they're at an inherent disadvantage, given the 500 MB/s ceiling of one second-gen lane that never gets hit in practice.