Abstract: An electronic system includes a circuit board, a first conducting element, a second conducting element and at least one connecting element. In this case, the circuit board has at least one through hole and at least one grounding unit disposed around the through hole. The first conducting element is disposed on one side of the circuit board, and the second conducting element is disposed on the other side of the circuit board. The connecting element is disposed through the through hole for connecting the first conducting element and the second conducting element.

Abstract: An electronic system includes a circuit board, a first conducting element, a second conducting element and at least one connecting element. In this case, the circuit board has at least one through hole and at least one grounding unit disposed around the through hole. The first conducting element is disposed on one side of the circuit board, and the second conducting element is disposed on the other side of the circuit board. The connecting element is disposed through the through hole for connecting the first conducting element and the second conducting element.

Abstract: A fixing component of a main board comprises a connecting part, a thread-assembling part and a fixing part. The connecting part has a first surface and a second surface, wherein the first surface is disposed opposite to the second surface. The thread-assembling part is disposed on the first surface of the connecting part. The fixing part is disposed on the second surface. The connecting part and the fixing part are disposed on a main board by utilizing DIP technology and SMT.

Abstract: A connection device with plurality return paths includes a first connection component and a second connection component. The first connection component has a rectangular containing portion, a plurality of first pins and two first ground pads. The first pins are disposed at two long sides of the rectangular containing portion. The first ground pads are disposed at two short sides of the rectangular containing portion. The second connection component has a rectangular protruding portion corresponding to the rectangular containing portion, a plurality of second pins and two second ground pads. The second pins are disposed at two long sides of the rectangular protruding portion. The second ground pads are disposed at two short sides of the rectangular protruding portion. When the rectangular protruding portion is inserted into the rectangular containing portion, each first pin connects to each second pin, and each first ground pad connects to each second ground pad.

Abstract: An expandable heat sink is used for dissipating heat of a heat source on a main board. The heat sink comprises a main body and an expanded body. The main body comprises a main-body contact surface, which is contacted with the heat source, and a plurality of first fins. The first fins compose a main connecting portion. Furthermore, the expanded body comprises a plurality of second fins and the second fins compose an expanded connecting portion. The expanded connecting portion is removably connected to the main connecting portion.