Just a thought, instead of measuring the time it takes the water to heat from a starting temperature to an ending temperature, could you instead measure the heat dissipated by a radiator. You could set up a regular water cooling loop (pump, fans, and radiator) and measure the temperature of the water in and out of the radiator. Assuming that the CPU and cooling loop are at equilibrium and the loop is large enough not to bottleneck the heat transfer, wouldn’t the heat being kicked off by the CPU be the sum of the heat in the loop plus the heat kicked off by the radiator. I’m still debating with myself what equations would need to be used. I kind of think it would involve using integrals to find the area under the curve of the temperature of both the loop and regulator. Any thoughts?