sisctrl is a gtk-2.x based tool for the XFree86/X.org SiS ("sis") driver to tune the display parameters during X server run-time. Among other features, it allows switching and changing output devices, tuning TV output, gamma correction and Xv (hardware video) properties. It also supports switching the display mode and resizing the desktop using the RandR extension. WWW: http://www.winischhofer.net/linuxsisvga.shtml#23