No, they have 4 memory channels per Socket, and can use up to 2 DIMMs per channel. So provided only one DIMM is user per channel, this can fully utilize the meo

No, they have 4 memory channels per Socket, and can use up to 2 DIMMs per channel. So provided only one DIMM is user per channel, this can fully utilize the meory bandwidth of a single socket. (It also depends on the memory module having enough ranks to provide enough internal parallelism, but the effect of that only shows in small memory accesses).