Specifications: Can accurately, stably and fast find computer failures. The code value of "Start Code" is specific "0000" or "FFFF", which is at a glance. Use the four-digit fault code to display. With ming-sound to report faults function. Anti-insertion or misinsertion will not burn any parts. Suitable both for ISA bus and PCI bus. Not inserting the CPU and other empty board, just power on to diagnose important signal situation in the board. Can fully compatible with all kinds of high, medium and low-grade motherboard (for Intel, AMD and other manufacturers' low, medium and high-level and server CPU platform motherboard). Indicator Function: CLK: No matter ISA or PCI, as long as there is a empty board (no CPU etc.), the light should be on when power on, otherwise, the CLK signal is failure. BIOS: Motherboard running, the light will flash while there is a reading operation on the BIOS. IRDY: The light will flash when having a IRDR signal, otherwise, it will not light on. OSC: Empty board powered on, the light will be constant on, when there is the ISA slot have main vibration signal, otherwise, failure of oscillation. FRAME: The light will flash when there is circular frame signal. Light will constant on in peacetime. RESET: power on or press the RESET switch, the light will be on for half second and then be off. Because, if light is not off, the reset pin on motherboard connected to the acceleration switch or the reset circuit broke down. 12V: Empty board powered on, the light should be constant on, otherwise the voltage or motherboard has a short circuit. -12V: Do ditto. 5V: Do ditto. -5V: Do ditto (only for ISA slot). 3V3: This 3.3V voltage is unique for PCI slot. Empty board powered on, the light should be constant on. Some of PCI slot motherboard has not this voltage, the light should be off. Type: PC Analyzer Material: PC Features: 4 Digit, LCD Display, Motherboard Diagonosis Size: 10cm x 10cm/3.94" x 3.94" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Diagnostic Card 1 x English User Manual