Memory subsystem with narrow bandwidth repeater channel

A system, comprising:

• a memory controller circuit to control access to memory;
• a first memory module to couple point-to-point to the memory controller circuit via a first group of signal lines of a memory channel between the memory controller circuit and the first memory module, the first memory module including a repeater;
• and
• a second memory module to couple to the memory controller circuit through the repeater via a second group of signal lines to couple point-to-point between the first memory module the second memory module, wherein the second group of signal lines includes fewer data signal lines than the first group of signal lines, to support a lower bandwidth than the first group of signal lines on the memory channel;
• wherein the repeater is to repeat signals on the memory channel between the first group of signal lines and the second group of signal lines.