If you are running VM’s for SharePoint 2013 and Windows Server 8 (beta), there’s a good chance you have installed the VMware Tools. There is also a good chance that after you did that your VM went black. Amanda just noted this fix to the issue:
http://mytricks.in/2012/03/solved-windows-server-2012-black-screen-after-installing-vmware-tools.html – long story short, enable graphics accelleration in the VM and reboot. Should solve the issue.
Hope it helps