Hi,
GPU Passthrough means that the guest OS gets direct access to the graphics adapter.
In that case the guest OS directly controls the GPU and you need another GPU for the host OS.
VMware Workstation does not support GPU passthrough.
With 3D acceleration the guest OS gets access to a virtual GPU that understands GPU specific features such as DirectX. The VM driver+virtual hardware translates the 3D accelaration commands that it receives and executes those on the GPU hardware. Since VMware Workstation 15.5 it uses a special sandboxed process for that.
A relevant blog post is here:
https://blogs.vmware.com/workstation/2020/05/directx-11-now-with-workstation-tp20h2.html
Note that this was about a beta which is now part of VMware Workstation 16.x (as well as 15.5.x)
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Wil