device: 0.908 boot: 0.852 other: 0.814 graphic: 0.678 semantic: 0.674 PID: 0.550 network: 0.500 debug: 0.468 performance: 0.455 permissions: 0.408 vnc: 0.392 files: 0.391 socket: 0.373 KVM: 0.083 ovmf + smp + hyper-v + windows 7: doesn't work - using ovmf - enable smp (>1 processors/cores) - enable hyper-v features (eg. -cpu Haswell,hv_time,hv_relaxed,hv_vapic,hv_spinlocks=0x1fff) - try to boot or install windows 7 x64 Result: black screen and hangs Sigh, the Windows bug that keeps on giving. And, users avoiding libvirt and sticking with the QEMU command line, despite the fact that using libvirt & its tools would save them from this bug. Anyway, this report is a duplicate of ; please read that one for the background. Closing this one as invalid (just like the other one). Thanks.