Radio X, referred to as Radio:X in its logo, is an alternative rock/heavy metal/grunge music station in Grand Theft Auto: San Andreas. It is hosted by Sage, an escaped mental patient who holds extremely pessimistic world views. A proud member of Generation X, she is very outspoken against the previous generation and constantly speaks her views on air between songs. Like other DJs, Sage's comments change as the game progresses (though only after the Los Santos Riots begin will she take an interest in current events, and in addition she will often be heard announcing the arrival of weather systems such as fog and thunderstorms. It is based on the real-life radio station X103.9 - "The I.E.'s Alternative Rock"
The "X" in Radio X is reference to the "X" generation, people that were born in the late 70's and early 80's, which they be in their late teen or early adulthood in the early 90's. It also reference of the teen and adults that listen to Alterative music at that time.
Sage is her real name, as reinforced in the intro to Danzig's "Mother" saying "Yes, Sage is my real name, and if you don't believe me, you can go fuck yourself!"
Sage also says the reason she calls herself Sage is because she can't remember her last name.
The station is the default station when the player enters a Buffalo or PCJ-600.
In real life, there is a real Radio X called Choi Radio X in Quebec City in Canada.