Need help with trifire

[D_5]

Hi I have an Asus Maximus V extreme motherboard and 3 Sapphire 7970 6GB Vapor x cards. I just got my 3rd card today but I can't seem to make it work. Enabling it disables crossfire x and then I only run 1 Graphics card. Only 2 graphics cards show up in device manager. I have swapped the cards around all are working and crossfire with 2 cards work fine. I have set the crossfire bridges one the first slot to the second cards firs slot and from there the second slot to the third cards second slot. Does the motherboard support graphics cards in the first PCI and then the third and the fifth slot? I also have uninstalled all the drivers and downloaded new ones. I am really stuck on this any ideas?

[kkn]

http://www.moddiy.com/product_images/z/103/riser_cards_400__00039_zoom.jpg

http://www.ebay.com/itm/1X-PCI-E-Express-PCIe-x16-Extender-Cable-Riser-Card-Molex-Power-Solid-Capaci...

there you see how it looks like.

[D_5]

Awsome will try thank you for all your help. I have indeed concluded that it is the black slot that is the problem. I can't crossfire 2 cards if it is in the 3rd (black) and the 5th (last slot)

[kkn]

you have to use all 3 red slots, not black. ( 1 and 2A and 3 )
the black ( 2B ) will be disabled when slot 3 or 4 ( red ) is populated.