List two or more features of the motherboard that might make it difficult to upgrade?

Several features of a motherboard can complicate upgrades, including the type and number of expansion slots available, which may limit compatibility with newer components. Additionally, the chipset can restrict support for the latest CPUs and RAM types, making it challenging to find compatible upgrades. Furthermore, the physical size and layout of the motherboard can also pose issues, as larger components may not fit in smaller cases.