A method provides improved signal quality in a computer memory system. In one embodiment, a digital signal is generated having a voltage interpreted with respect to a reference voltage. The reference voltage is dynamically adjusted as a function of the traffic intensity at which the digital signal is directed to a particular receiver. A training phase may be performed for each DIMM of the memory system, to construct a lookup table correlating suitable reference voltages with different traffic intensities. The lookup table may be referenced during a subsequent execution phase, to dynamically select a reference voltage according to changing traffic intensity. The dynamically selected reference voltage value may be enforced by using transistors to selectively recruit resistors of a resistor network.