Here is a good explanation of Device Guard from Dell:
Device Guard is a combination of enterprise-related hardware and software security features that, when configured together, will lock a device down so that it can only run trusted applications. If it is not a trusted application, it cannot run. When configured, it will lock a device down so that it can only run trusted applications that are defined in your code integrity policies. Device Guard is dependent on Virtualization based security (VBS).
If it states that it is Windows 10 Pro, then just clarify that it's 64 bit with the vendor. Most ship with 64 bit, but I would inquire about this. On their site it should state whether it is 32 bit or 64 bit, but a quick and easy e-mail to the vendor support/sales might help you clear this up.
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