The Raspberry PI is a SoC with on-chip DRAM. A relatively new development in SoC implementation.
Die stacking (putting two pieces of silicon in one package) enables short connections between main memory and logic.
Growing technology maturity allows DRAM to be put on the same silicon die with the SoC logic.
Memory density is still going up, even if CPU core speed has stalled.
| 57: (C) 2008-16, DJ Greaves, University of Cambridge, Computer Laboratory. |