#22, PCI Express x16 Slot (PCIE2) This is where you would install your new video card.
Your video card will have 1 or 2 sockets at one end, (depends on the power required by the card) This is where you plug in a cable DIRECTLY from the Power Supply.
There is no power cable from the video card to the Motherboard.
#4, ATX Power Connector (ATXPWR1) 24 pin main power connector.
#24, ATX 12V Power Connector (ATX12V1) 4 pin power connector from the power supply. (not used for video)