PURPOSE: To refer to the content of abnormality later by grasping the content of abnormality when a system starts, displaying it on a panel and storing it in a magnetic disk in the computer system having a device group including CPU, a main storage device and input/output controllers.

CONSTITUTION: Constitution information on the device group connected to the system is previously stored in a flexible disk device 2 as a resource table 4. When the system starts, a system controller 1 reads the resource table 4, reads initial status from respective devices and generates an initialization table 5. The initialization table 5 is stored in the flexible disk device 2. The content of the resource table 4 and that of the initialization table 5 are compared a comparison part 10, and the result is displayed in a display part 12. Thus, a starting result when the system is shifted can securely be grasped. The initialization table 5 can be read later and can be displayed in the display part 12.