Some applications are able to use the vGPU/GPU (indicating the VM is configured correctly), maybe Chrome, WebGL benchmarks, however some such as Office 2010 do not.

Debugging

• Other reasons a GPU may not be used: CTX202149 - Known Issues or Configuration Reasons: OpenGL/DirectX/GPU Acceleration Not Used

Problem Cause

A user/group (for ICA/RDP) policy disabling Hardware acceleration for Office 2010/2013. This is often done in deployments where no GPU is present in the XA VMs. 

This KB explains a situation where some applications, such as Microsoft Office 2010/2013, do not use the configured GPU/vGPU in a Citrix HDX environment, even though other applications (for example, Chrome or WebGL applications) successfully utilize GPU acceleration.