The advent of switching power supplies, while advantageous from a size and efficiency standpoint, presents major problems for the grid. The off-line part of the power supply design may not have changed significantly since the days of linear regulation. It is still comprised of a transformer, rectifier, and capacitor, but it now feeds one or more switching regulators. This creates poorly shaped waveforms with higher frequency switching noise capable of making it back into the current drawn from the wall. Additionally, the shift in effective current peak away from that of the voltage waveform in time introduces high-harmonic-content switching waveforms that potentially worsen the distortion of the current waveform. The net effect is a very low power factor if not addressed through corrective design measures.