Pete has a 2013 Mac Pro and he's trying to dual boot in Windows with BootCamp, but it won't work. Leo says it's probably a driver issue. When using BootCamp, it loads Apple's drivers. If the drivers are bad, then the OS can't talk to the hardware. So if Apple doesn't have drivers for his version of Windows, he's out of luck.
Running Windows virtually is another story. A virtual app like Parallels can act as a middle man that 'tricks' the OS into believing it's a Windows machine.
Apple has a support page for BootCamp to show what it supports. Pete should go to the Apple support site and download the right version of BootCamp, then Windows 8 64 bit. He should update everything as well.