YouTuber Equallo took it on himself to transform an old NES he found in an alley where someone had thrown it out (!) into a functioning gaming PC. As he points out in the first of his videos documenting this process, while other people have turned Nintendos into gaming PCs in the past, he hasn't seen anyone do it in five years or so and was interested in giving it a go with 2020 hardware.
That means he tried to get an CPU AMD Ryzen 2600 and an Nvidia GTX 1660 Super GPU in there, and a power supply to match. To do that, and to get the power and reset buttons working, he had to cut out "a good portion" of the cartridge slot and remove the crossguard from the bottom for a little extra depth, as well as getting creative with the height of the finished thing as he explains in the second video.
I have to wonder how that old plastic's going to handle the heat this thing will pump out, but I live in Australia and once saw someone bolt a pizza oven fan onto the side of his rig to deal with summer, so I always assume everyone's PC is on the verge of overheating. Obviously practicality isn't the point—this is a demonstration piece, a conversation starter and a cool thing to have sitting on a shelf where you can plug it in and say, "Let's play Crysis on my Nintendo."