The is another hardware controller made by Promise Technology, designed to manage Serial ATA (SATA) and Parallel ATA (PATA) hard drives in your computer system. The model TX4 and TX2plus 579 refer to specific versions of this controller, which allow multiple hard drives (SATA or IDE) to be connected to your system. These controllers also enable RAID functionality, allowing you to set up multiple drives for better performance, redundancy, or both.