Methods and apparatuses for calculating the location of an optimal sampling point for a receiver system are disclosed. In brief, a first method comprises determining a maximum voltage margin and a maximum timing margin of a received signal, and from these margins, determining an optimal sampling point, which includes a reference voltage level (Vref) and a relative sample phase. The location of the optimal sampling point is based on the locations of the sampling point of the maximum voltage margin and the sampling point of the maximum timing margin. A second method comprises establishing an initial sampling point, and then successively refining each of the voltage and timing components of the sampling point until an optimal sampling point is reached.