The Tango PCI Express Controller driver is a software component that enables communication between your operating system (usually Windows) and the Tango PCIe controller hardware. PCI Express (PCIe) is a high-speed interface standard commonly used for connecting expansion cards, storage controllers, network adapters, and other peripherals to a computer's motherboard.

The Tango PCIe controller could refer to a specific controller chip from a hardware manufacturer (for example, a storage controller, network card, or other PCIe interface devices), but without more specific details about the exact device, it's usually safe to assume it's related to a PCIe device that requires a driver for proper operation in Windows.