Does a higher-wattage PSU automatically draw more power in comparison to a lower-wattage PSU even if the components fed by the PSU remain the same?
The reason I'm asking is that I'm thinking of getting a PSU with more wattage than currently necessary for my server, to make expansion (e.g. additional CPU) later easier without having to exchange the PSU.
Best Answer
A bit, yes.
Computer power supplies typically become more efficient the closer they are to their rated capacity, so if you're running a large power supply with a low load, it's going to be less efficient than a properly-matched power supply.
How exactly this translates into power/cost savings, though, is highly dependent on your environment.