Highpoint RocketRAID 3522. Supported hard disk drive interfaces: Serial ATA, Serial ATA II, Host interface: PCI Express x8. Internal memory: 256 MB, Internal memory type: DDR2. Data transfer rate: 3 Gbit/s. Processor clock speed: 800 MHz, Built-in processor: Intel IOP 81341. Mean time between failures (MTBF): 920585 h