It depends on the Virtual Machine you setup... remember that each VM has their own Driver Stack, by Default (unless you use pre-set such-as:
PS C:\> New-VM -Name VMDemo -Prerelease
The above will simply pre-setup a Full Windows 10 Pre-Release Environment., but you can always add a Graphics Card via below.
Now you can manually add this from within the VM or as part of it's setup with
PS C:\> Get-VMRemoteFXPhysicalVideoAdapter -Name *AMD* | Enable-VMRemoteFXPhysicalVideoAdapter
If you don't it will simply (Software) Virtualise the Hardware,. so that means the CPU not GPU will be running it as the VM has no idea there is a Graphics Card connected.