Wall Street models AI data centers in dollars per gigawatt. Roughly $50 billion each. That misses the variable that matters most: time. SpaceX stands up a gigawatt in about six months. Neoclouds like CoreWeave and Nebius take closer to 18. That gap changes the capital math. A finished, contracted gigawatt starts generating cash and can be financed against. The faster you get there, the sooner the same money is free to build the next one. Picture two builders with the same construction loan. One finishes a house in six months, refinances, and starts again. The other takes eighteen. Over two years, the first builds two houses with that money. The second builds one. So the right metric isn’t dollars per gigawatt. It’s dollars per gigawatt per unit of time. On that measure, $50 billion buys SpaceX roughly twice the compute it buys a slower builder. Capital efficiency on a timeline. Not intuitive, and it’s why build speed is worth more than it looks. $SPCX