NVIDIA's core series of graphics cards

GF is GEFORCE

Geforce is an English product trademark. (Geometry-Force=Geforce) GeForce is a series of display chips produced by nVIDIA. Currently, there are GeForce256, GeForce2, GeForce3, GeForce4, GeForce FX, GeForce 6 series, GeForce 7 series, GeForce 8 series, and GeForce 9 series and the tenth-generation "GeForce Positioned Models" series.