Double-layer rack

A double-layer rack comprising:

• a PCIe card frame having a PCIe accommodation space configured for receiving a PCIe-based card;
• a network card frame, wherein the PCIe card frame is fixed to and stacked on the network card frame, and the network card frame has a network card accommodation space configured for selectively receiving one OCP network card, two OCP network cards or one data processing unit;
• a PCIe riser card disposed on the PCIe card frame, and the PCIe riser card configured to be electrically connected to the PCIe-based card;
• and
• a network card connector assembly disposed in the network card accommodation space, and the network card connector assembly configured to be electrically connected to the one OCP network card, the two OCP network cards or the one data processing unit;
• wherein the double-layer rack further comprises a blocker component and a divider plate, the blocker component and the divider plate are selectively and removably disposed on the network card frame and located in the network card accommodation space, so that the network card accommodation space forms various accommodation space configurations for selectively receiving the one OCP network card, the two OCP network cards or the one data processing unit.