NVIDIA TAG Memory Tool

NVIDIA TAG Memory Tool

Can be useful…
You can download NVIDIA TAG Memory Tool HERE.

Strange DirectX application behavior on systems with at least 4GB of total available graphics (TAG) memory.

Some DirectX APIs are not designed to handle high memory conditions and will report far less memory than is truly available. This behavior is described in this Microsoft knowledge base article: Direct-X diagnostics tool (DXDIAG) may report an unexpected value for the display adapters memory.

Some DirectX applications will use these APIs to determine how much video memory is available and adjust their behavior (such as texture quality). Other DirectX applications, and all OpenGL applications, are unaffected.

On Windows Vista and Windows 7, NVIDIA provides GPU driver support to work-around this issue for GPUs with less than 3GB of memory. The workaround forces the video memory to the maximum amount these DirectX APIs can report, sacrificing some of the total memory. This is called “Compatibility Mode”.

The application “NvTagToggle.exe” linked below can help you detect this scenario and configure this workaround, as well as reset the GPU driver to its default behavior. The application is only supported on Windows Vista and Windows 7, for NVIDIA GPUs with less than 3GB of memory.



  • applications targeting windows vista or later should use the interface provided by DXGI to get the dedicated video memory and shared video memory values.
    accordingly to m$ ( check the VideoMemory sample in the DirectX SDK ) this is the way to get the most accurate values.
    the only problem that I think it might happen with DXGI is when you want to get the ammount of memory of a graphics card with more that 4GB of RAM (?) in a 32bits environment, since the return value resolves to a 32bit unsigned integer in this environment.

  • forgot to leave the link for the DXGI’s interface :)