[cdawzrd]

The latest high-end PCB tools actually provide useful autorouting features, because they have figured out that if you combine human ability to solve the difficult pattern-recognition and planning problems, you can have a computer solve the details.

For example, Xpedition's sketch routing feature: https://www.youtube.com/watch?v=fIi13gI9xEA

Routing 4094 signals sounds daunting, but it is a bit less daunting when you realize that a good fraction of them are power/ground (and route directly to planes), and the rest of them are mostly logically organized into buses/groups that can be routed together.

[astrodust]

Yeah, a good portion of those pins will be wired directly to the power regulator components that are next to the socket, and a good chunk more break out neatly into channels for memory and PCI-e.

Seems like it's almost boring these days since everything's encapsulated in a layer of abstraction. A lot of the more complicated wiring is in breaking out PCI-e channels into things like ethernet, audio, and other miscellaneous ports that involve good chunks of analog circuitry.