A computer device that includes a plurality of processor boards each provided with a processor, a memory, and a chipset, includes a first processor board that makes data in a cache, which have become unfixed as a result of an uncorrectable failure, invalid when the uncorrectable failure occurs on the first processor board in operation, and switches from the first processor board to a second processor board for replacement, and the second processor board that re-executes an instruction that was being executed in the first processor board when the failure occurred.