A high-speed serial computer expansion bus circuit topology, comprises: a first signal path connecting between a first interface and a second interface, a second signal path connecting between the first interface and a third interface, a third signal path connecting between the third interface and a fourth interface, a first selector circuit having a first passive element and a second passive element which are respectively disposed in the first signal path and the second signal path, a second selector circuit having a third passive element and a fourth passive element which are respectively disposed in the second signal path and the third signal path. The second signal path is conducted when the first passive element and the second passive element are conducted, the third signal path is conducted when the third passive element and the fourth passive element are conducted.