The present invention relates to the field of electronic circuits, and discloses a computer board comprehensive tester. The tester communicates with host computer software, and the host computer software stores signal encoding data and plug encoding data. The tester includes a signal simulation system , a load simulation system and a plug simulation system, the signal simulation system includes: a signal acquisition module, a signal processing module and a signal output module; the load simulation system includes: a load simulation module, a calculation module and a fault judgment module; the plug simulation The system includes: a data acquisition module, a matching module, and a prompt module; at the same time, a computer board comprehensive detection method is also disclosed; the invention integrates various sensor signal simulations, load selection simulations, and power integration, which greatly improves computer board maintenance. The feasibility, as well as the improvement of computer board maintenance efficiency and versatility, reduce maintenance costs for maintenance engineers.