Interesting question, what if everyone had a graphics card in their head instead of the human eye, visualization brain area, ....!
Current top GPUs consume 200 watts per hour, with 7.5 billion people it would be 1500 gigawatts per hour. Currently, ~ 21,000 terawatt hours of electricity are consumed worldwide every year. For the top GPUs, 16 hours a day per person would be: 16 x 200 watt hours per day 3.2 kilowatts are required for all 7.5 giga people it would be 24 terawatt hours a day, and for the year 8,760 terawatt hours of electricity, so we would then need around 42% more energy than is currently used. That would be an additional 2000 medium-capacity nuclear power plants that would have to be raised more.