When I try and load CentOS 6.9 the boot process hangs just as the Anaconda graphics is started for CentOS configuration.
CentOS 6.9 kernel does not have support for Skylake processors, I believe that there is an alternate arch SIG that "may" be able to compile 6.9 with a newer kernel or you may have to compile something using the kernel that is available from ELRepo.
Or use another graphic card that is compatible with the kernel that comes with CentOS 6.9.