A computer system is provided. The computer system comprises system and peripheral hardware devices, a display device and a chip. The display device comprises a display panel and an on-screen display (OSD) control module. The chip comprises a computer system environment information monitoring module, a control connection interface and a control module. The computer system environment information monitoring module monitors computer system environment information according to the system and peripheral hardware devices. The control connection interface is electrically connected to the OSD control module. The control module is electrically connected to the computer system environment information monitoring module and the control connection interface to control the OSD control module through the control connection interface according to the computer system environment information to further control the display function of the display panel.