what is PLL - A Phase Lock Loop (PLL) is a clock chip. A PLL is used to increase the fan-out and drive strength of the clock signal to the DRAMs and/or eliminate the propagation delay time of the address/control signals connected to the register of an RDIMM 

RAMpedia is a DRAM memory encyclopedia and reference tool
to help computer hardware board designers with DRAM memory subsystems.
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