Keep in mind the Channel when adding new RAMs in sockets The Dell PowerEdge T420 server has 12 DIMM slots. For optimal performance, it is recommended to install RAM in pairs of matching capacity and speed. We already have two 4 GB models placed in white DIMMS. We added two more so keep in mind the number that is mentioned on the motherboard DIMMS places. The system contains 12 memory sockets split into two sets of six sockets, one set per processor. Each six-socket set is organized into three channels. In each channel, the release levers of the first socket are marked white and the second black. NOTE: DIMMs in sockets A1 to A6 are assigned to processor 1 and DIMMs in sockets B1 to B6 are assigned to processor 2. Figure 35. Memory Socket Locations find PowerEdge-t420_owners-manual_en-us page# 69 RAM channels , specifically dual-channel and quad-channel memory configurations, are used to improve memory bandwidth and overall system performance. These configurations are ...