Back in 2004 my PC RAM was 256. My relative's laptop had 128. That's crazy when a modern CPU cache can theoretically host an OS (or even multiple OSes) from early 2000s.
The RAM prices are so high and the storage is also getting more expensive every day, so we're forced to fit everything inside the CPU cache as a solution! /s
The Power4 MCM had 128 MB cache in 2001. The G4 TiBook sold the same year came with 128 MB of system RAM base, and OS X supported 64 MB configurations for a few years after this.