The national electric code says not to draw more than 80% of the maximum load a circuit can handle continuously. So assuming you plan to game for a reasonable amount of time we’re limited to 12 amps.

That’s 1440 watts. And power supplies for PCs these days seem to be 80-95% efficient for good ones. Let’s say you’ve got a 90%er.

That’s 1300 watts. A top end CPU is 120 watts. Looks like 70-130 watts for a motherboard. Call it 100.

We’re at 1080 watts. Four sticks of DDR5 is another 60 or so. Let’s add 20 for two M.2 drives.

Wait, didn’t we have a 600 watt GPU? Down to 400 left. Good thing dual GPU gaming is dead, we can’t afford a second in our killer gamer system. Let’s add 20 watts for fans so everything doesn’t melt.

So 380 watts left out of 1440. That’s just 25%. But no spinning hard drives or SSDs, no USB PD, no PCI-e cards at all but our one graphics card.

Wait we need a monitor on the same circuit. Looks like that’s 50 watts for a high end LG, 330 now. You did only want one monitor right?

Is it really that hard to imagine hitting that limit soon?