Not always. Tcase temperature has a lot to do with what cooler you have and how well your thermal interface material has been applied. If heat can't transfer to your heat sink in an efficient manner, the delta between core temps and tcase can shrink. Use a program like Everest to tell you the "CPU" temp. You can also use SpeedFan to get Tcase temps, but it will need to be calibrated before hand to get an accurate reading.