A computer system has a central processing unit, a north bridge electrically connected to the central processing unit, memory electrically connected to the north bridge, a south bridge electrically connected to the north bridge, and a peripheral device electrically connected to the south bridge. The changes can vary to such an extent that the slightest differences in the influences can be can be registered with the highest sensitivity. A first analysis result is built on an earlier section of historical data, and a second analysis result is built with more recent historical data.