NVPlay

NVPlay is a tool designed to allow low-level communication with and control of graphics hardware, focusing on early Nvidia GPUs from the mid to late 1990s. It is a tool intended for developers to aid emulation efforts. The program will initialise your installed GPU in an entirely freestanding way without any drivers and has several modes that allow different methods to control your graphics hardware. By default it kicks you into a REPL loop that lets you run a set of commands that do register-level GPU I/O.