z87 g45 confirmed working with 7 R9 280x cards. z87 g55 and z87 mpower should work fine too.
Rig config :
- windows 8.1
- lbr modified 3.12 amd drivers
- All cards on 1x 16x usb risers.
z87 g45 don't have 7 pci e
btw what is the best card with 6 pci e slot? i don't need the risers, i'm planning to do a different kinda of mining