From what I understand and some info in the backl of my mind from an article a while back........
Marvell controllers use the PCIe bus.
Intel is embedded into the Southbridge chip on most MOBOs.
Therefore Marvell is limited by the PCIe Bandwidth. This also means Marvell does not perform as well in RAID setups.
EDIT: Curiosity got the better of me...
robbed from here
"Results in bandwidth speed tests for the Agility SSD were very similar to the IOPS benchmarks. The X58 and P55 platforms produced roughly 222 MBps reads and 165 MBps writes, all while connected to the Intel ICH10 Southbridge. In comparison, the Marvell SATA 6G controllers produced approximately 154 MBps read speed, and 106 MBps write. This results in a 42% advantage for the ICH10 SATA 3G controller over Marvell's 9123/9128 SATA 6G controller in read speed, and a 55% advantage in write-to performance. Why, you might ask? It's all in the driver.
You see, Intel's ICH9 and ICH10 chips utilize a driver architecture that creates a virtual RAM-disk buffer for cached transactions. The amount of RAM-disk created depends on the chip and available system memory (which we detail in our spin-off article), but the combined driver refinement and memory cache capability lead to very high performance. This is where Marvell needs to grow, and do more than a simple reverse engineering Intel's work in creating their own driver."Edited by Mattyd893 - 4/13/12 at 5:31am