100% Brand New and High Quality LCD display shows error code, cause, and solution on screen in English. No need for an error code manual, making it much more practical than LED hexadecimal displays. Compact design for easy portability. PCI interface for easy access to your desktop PC. Ideal for IT enthusiasts and engineers for testing and repairing computers. Insert into the PCI slot and set the correct BIOS with the BIOS button before booting. Quickly displays error code, cause, and solution after booting if there's an issue. Compatible with AMI, Award & Phoenix BIOS. BIOS button to set the correct BIOS and PAGE button to display posts. SYS, CLK, +3.3V, +5V, -12V, +12V indicators are available. The indicator light shows the power status of the board as per the table below: 12V PCI Slots: 12V Power Supply Indicator LED -12V PCI Slots: -12V Power Supply Indicator LED 5V PCI Slots: 5V Power Supply Indicator LED 3.3V PCI Slots: 3.3V Power Supply Indicator LED SYS: System Operation Indicator Light, blinks in normal state. CLK: When the clock signal outputs, dim light in normal state. PAGE Button: Short press to jump to the previous code; long press to jump to the previous five codes. BIOS Button: Short press to switch current "BIOS"; long press to save the current selection.