A method and system are provided for coupling a DRAM and a memory controller during driver training to reduce mismatches by controlling impedances within the system environment. The memory device, which is typically the device initializing a bit level voltage on a data net, is adjusted through altering what appears to be the reference voltage value to the memory device. A current driven to the memory device is varied in small increments while impedance training is rerun until a desired value is achieved to set the 0 level voltage on the data net.