The human brain fires at 600hz with 1000 synapses on average and 86 billion neurons. Taken together, there's about 56M Gflops assuming firing dumping chemicals into synaptic gap and being summed as a potential on the dendritic surface is a Flop. That's 56 PFlops. That would take about 175 RTX 3090Tis. That many 3090Tis would consume 78Kwh or 100HP. The human body in total puts out 1/4HP so we are 400x as efficient as a silicon computer of similar compute capability, assuming that there are no efficiency gains to be had by normalization, etc.