It's not a dumb question, but it's so broad that it would take at least an entire textbook to fully answer it. Just off the top of my head, some possibilities

It's not a dumb question, but it's so broad that it would take at least an entire textbook to fully answer it. Just off the top of my head, some possibilities are: * More cores * More numerous/powerful execution units that can do e.g. vectorized math * Architectural features such as virtualization and security defenses * Bigger and more flexible caches * Complex pipelining/out-of-order/speculation logic that allows more instructions to be executed (on average) per clock cycle * Special-purpose functional units that dramatically accelerate particular applications (e.g. AES encryption, video encoding/decoding) and are idle the rest of the time * Replacing "deep" networks of logic gates with equivalent "wider" ones, which occupy more die area but have a shorter critical path, enabling faster clock speeds