So I've been trying to get pci passthrough to work now for a week I've gotten everything working. Gpu drivers are installed in the guest os(Windows 7) and I can play games. The only problem is I have to use the opensource Ubuntu amd drivers on the host, if I use the property fglrx drivers the kvm says the device is busy even though 'lspci -vnn' says the card is assigned to vfio-pci as the driver in use. So clearly there is something wrong with amd's drivers that's causing the card to be busy. I've contacted amd about this and waiting for a reply. Until then I was wondering if anyone knows a workaround this without using the opensource drivers I want to use the fglrx drivers.?
Mobo: Gigabyte GA-990FXA-UD3
GPU: R9 280 x2