Microsoft says that you have to be using either Intel VT or AMD-V hardware in order to run Hyper-V. Elsewhere in the Hyper-V documentation, you can read that the required support is "...either AMD64 or Intel IA-32e/EM64T (x64) processors with hardware-assisted virtualization support." (Itanium processors are not supported.) Interestingly, it isn't all that easy to discover whether a given machine meets the prerequisite.
Thinking it was time to buy a new laptop to use for experimenting with Hyper-V, I went to Dell's website and typed in "Intel VT" to the search engine. Sorry, no results were found. AMD-V? Same result. Thanks Dell! OK, I'll try the Intel site. Lots of hits - this is more auspicious. After a little scanning, I found the Intel Virtualization Technology page. Yesss! But...no link to processors that support Intel-VT. There's a whitepaper that looks promising... until I open it and find it was written in 2005. More white papers, some old and some super old, but no details on which processors support Intel VT. Come on - I'm at the Intel VT home page, fuhpetessake, and there's no link to a list of supported processors? I know that you can't just assume that all Core 2 Duo processors support Hyper-V, because there was a stink over in China recently about a delivery of Core 2 Duo systems that didn't.
Time for Wikipedia. At least here I get some data: "The Core 2 branded processors featured the Virtualization Technology (except T52x0, T5300, T54x0, T55x0 with stepping B2, E2xx0, E4x00 and E8190 models)...". That's at least a starting point. Of course, I still won't know whether the virtualization feature is fully supported by any given system's BIOS. Note to manufacturers like Intel and Dell: Think about telling your customers which of your systems will support Hyper-V. And save them an hour or two playing Sherlock Holmes. We've all got better things to do!