The T6600 does not have "virtualization" (VT) capability. Does SU7300 have it?
According MicroSoft test routine, Virtualization is essential for Windows7 premium upgrade to Professional. Only Windows7 Professional provides "XP-mode" capability, which helps you not to be forced to buy future upgrades to your current XP programs.
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Use VMlite XPmode, it does not requires CPU's with Virtualization.