This tester is used to check the presence of open/short circuits or masses on connectors of a graphics card on a motherboard. Instant visual test by LED diode tray. Compatibility: Any graphics card in AGP or PCI Express If the graphics card is not displayed when repairing the computer image card, the screen is blurred, etc., first check whether there are obvious burn spots, whether the board is obviously disconnected and whether the group voltage is normal When repairing computer image card errors, screenless, blurry or unstable screens, you don't need to use a multimeter to measure the PCI bus interface between the golden finger of the picture card Add a 12V power supply to the tester, plug the error card into the corresponding slot, press the pressure switch in the upper right corner, the corresponding indicator on the tester should light up, if it is not turned on or flashes, the brightness changes significantly, or caused by the open circuit or short circuit of the CPU main chip, use the universal meter to further determine the error point