A circuit board includes a base board defining a number of via holes, a power supply connection unit, a load connection unit, and at least one capacitor connection unit(s). Each of the at least one capacitor connection unit(s) includes two capacitor connectors, and one of the two capacitor connectors is positioned nearer to the power supply connection unit and farther away from the load connection unit than the other. The via holes are divided into at least one group(s) corresponding to each of the capacitor connection unit(s), and all of the via holes in each of the group(s) are equidistantly positioned along a semicircle arc surrounding the capacitor connector of the capacitor connection unit corresponding to the group that is positioned nearer to the power supply connection unit.