Does data center spending resemble investment in fiber and railroads?
Core argument: GPUs face a replacement cycle of 3–4 years at best, unlike long-lived assets such as backbone fiber and railroads, making data center capital expenditure different from those earlier buildouts.
Capital expenditure on data centers is very different from spending on fiber and railroads. Railroads and backbone fiber are long-lived assets. This is not the case with data centers. Almost all aspects have declining utility over time. First, and most obviously, the GPUs running and being used for training or inference purposes. The replacement cycle for GPUs is 3-4 years, at best, nothing like fiber or railroads. To turn it around, if you create a data center today and don't use it for four years, it would be better to never turn on the power. It's largely been superseded by subsequent technologies. Data centers also require power and water, and those connections, within reason, are useful longer. The outer shell—some would call it a building—also has a longer life. But most of the cost in a data center is not in the shell, or power, or cooling water. It is in the processors. And having to replace them every few years creates intense pressure on the investment. You must earn a high enough return before replacement to justify the expenditure. In financial terms, your income must exceed the risk-adjusted, weighted average cost of capital, which runs 12-14%.



