Abstract: The present invention relates to a D-subconnector provided with ferrite cores, formed in the opposite ends of a computer signal cable which connects to a computer body and a monitor. More particularly the plurality of ferrite cores are incorporated in an interior of the D-subconnector, and a copper plate is inserted between the cores. This configuration substantially attenuating magnetizing action. Additionally, the copper plate can achieve common grounding inside the D-subconnector. Moreover, the present invention can obtain an E.M.I. effect while obtaining clearer images and reducing the occurrence of a short-circuit.