Very first link from a Google Search of "AMD Athlon II M300"
http://products.amd.com/en-us/Notebo...il.aspx?id=583
The Processor's manufacturer will list the specs for it. Notice in the table, the section
Virtualization Yes
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Just because the processor supports VT extensions does not mean the OEM will let you have the option in the BIOS. Quite a few notebook makers and some Desktop motherboard makers will disable this feature. It's better to contact the actual notebook maker, or at least search their support docs to find out for sure if VT extensions are supported on that model.