If you're interested in learning more about AIO runtimes, here are some resources to get you started:

A pump running at 4800 RPM (Asetek Gen8) moves more water but introduces whine. A D5-style pump in an AIO (rare) runs at 1800 RPM silently. "Runtimes" here refer to how long you can tolerate the acoustic footprint. ComputerBase frequently logs pump noise in Sone (not just dB) to determine if a cooler is suitable for silent runtimes (e.g., overnight rendering).