Vt-x is Enabled in Bios and it shows working in Intel Processor identification utility. but I'm not able to run 64-bit Guest OS on both VirtualBox & VMware Workstation.
Virtual Box says
VT-x/AMD-V hardware acceleration has been enabled, but is not operational. Your 64-bit guest will fail to detect a 64-bit CPU and will not be able to boot.
PS : I have not enabled the Windows 8 Hyper-v feature