Comment by vbezhenar

There are Intel CPUs which come with bundled RAM. For example Intel Core Ultra 5 238V. It's like SoM: RAM is mounted directly on the CPU package, not even soldered on the motherboard. I'm not sure what particular advantages does that bring over traditional packaging, maybe shorter wires to allow for faster turnarounds between CPU and RAM. But there's zero chance of upgrading or replacing RAM for sure.