A methodology is described for testing the NS32532 32 bit microprocessor to increase the yield and reliability. It is based on an intensive use of test data collection, continuous use of data analysis, and various failure-analysis methods. The use of the methodology enabled the authors to locate easily process problems and topographies that are sensitive to process marginalities and can be easily modified to increase yield. They also identified circuit sensitivities, speed problems, and test instabilities, which enabled them to increase the speed and the overall yield of the product as well as the test reliability