When I do that it works with that one card but when I add the rest of the cards individually they are not detected and the fans work on them so there is power on the risers.
I can connect 2 cards in the 2 x PCIE 16 slots but when I connect a riser to the 1x slots for the 3rd card it does not detect it as well
Youve got three choices here...
1. Your riser is ether defective or you pci 1x slot is defective, Sometimes you have to set up your bios to detect a graphics card through the pci 1x. you need to check into this.
2. Your power supply cannot handle all your graphics cards.
3. Your video graphics driver is out of date or one of your cards is incompatible with the rest. Make sure you give your pc windows time to configure your system and check to see if all of them are listed in the device manager.