help| Windows 7 cant recognize 8 gpu

so i receive my own rig after many weeks of waiting , yeaye

so heres my problem,
i am running win 7 pro, with 128gb of ram , 2 xeons and 8 1080 of PNY cards
the rack/mobo is FT77CB7079
windows 7 does recognize the 8 gpu BUT only 6 are actualy working, when opening device manager it shows that 2 of the gpus are having some problems, "Cannot Find Enough Resources" error 12.

what i did:
i tested each pci separate , works fine
i tested each card separate , works fine
update the bios to latest version

help will be appreciated

(UPDATE)

i forgot to say that i've tried on linux (centOS) and the cards works fine.