There were four basic materials that the Egyptians used to build the pyramids: limestone, pink granite, basalt, and alabaster. Each type of material had a diverse use. Limestone had, for the most part, two uses.
To answer your question: The useful lifespan of a CPU is about 3-4 years. My guess on the technical lifespan under full load is closer to 8-10 years if nothing else breaks and takes the CPU with it. The reasons: High Performance Computing Clusters usually keep the computers for 3-4 years.
A laptop computer battery should last between two and four years, or around 1,000 full charges. The total lifetime of battery life is dependent on the type of battery your laptop has, how you use the battery, how it's charge, and how well you take care of the battery.