Power reactor benchmark calculations using the advanced code package CASMO-3 /SIMULATE-3 with new models have been performed for nine cycles of Chinshan Unit 1 and six cycles of Kuosheng Unit 1. The fuel reload designs include gadolinia as a burnable absorber, natural uranium axial blankets, and fuel from different vendors. The calculated results for cold critical tests and traversing in-core probe (TIP) responses are compared with measured data. These comparisons show that the new modeling accurately predicts important physics parameters for power reactors, and it is more accurate than the conventional model. However, more studies of the TIP adaption model are needed in order to gain more experience for its application.