The atx power port support 12V power. Please connect the extral power for your PCI-E card if the power is insufficient. (The switch is for ATX power) ^^ The converter support all standard PCI-E 16x 8x 4x card, like USB, LAN, 1394, Audio, Graphics Card. ^^ One PCIE PCI-Express 16x 4x device can be connected, The converter can be installed into the system internally through the SFF-8611/8612 oculink interface. ^^ This oculink pci-e converter enables belowing applications. ^^ Oculink 4x connectors are internal and external small form factor PCI-E connectors and cables optimized for the client and market.