US Patent 9298228 Memory capacity expansion using a memory riser

A computing system having a memory riser sub-system. The computing system includes a motherboard with a memory module connector and a riser card inserted into the first memory module connector. A first mezzanine card is connected to the riser card. The first mezzanine card includes a first mezzanine memory module connector for a first memory module and a second mezzanine memory module connector for a second memory module. A memory channel electrically connects the memory controller to the first mezzanine memory module connector and the second mezzanine module connector via the motherboard, the first riser card and the first mezzanine card. The memory channel may be divided into a first data sub-channel connected to the first mezzanine memory module connector and a second data sub-channel connected to the second mezzanine memory module connector.