Before testing, make sure your CPU and memory are working properly, you can try them on other computers to make sure they are working properly. Don’t put on all your accessories at once. You can try CPU, memory and screen first. Whether the Caps lock button works is the dividing line between whether the motherboard works or not. If the Caps lock button can be switched, it is almost certain that the CPU, memory, and motherboard are working. At this time, pay attention to the problem of the LED display. Most importantly, all accessories must be removed without electricity, otherwise it may burn the accessories. 1, switch work. That means the motherboard works. Please check the screen. Cannot switch. Please check the CPU and ram. [About Quality] This motherboard has been professionally inspected and tested by qualified suppliers. Before shipping. We’re gonna run a full test on the motherboard. The test included the screen, keyboard, battery,and all USB and output ports. Please check your original part before purchasing to ensure that your part number matches the part number listed in this item title.