Hi YellowPixelHD, this behavior is normal because your processor is not overclockable. Intel® Extreme Tuning Utility was designed for unlocked Intel® Core processors.
Can I unlock it?
You can only overclock Intel® Core processor models ending in K or X, such as:
Please note most of these unlocked Intel® Core processors are designed for desktop systems.
Some processors for laptops are not meant to be replaced or upgraded because they are soldered to the board; however, compatibility and upgrade information comes from the motherboard or computer manufacturer because they test and validate their products with our processors and not vice-versa.
By the way, your processor is better than the Intel® Pentium D 945 you linked above.