Things about DXVK you must acknowledge:

• DXVK improves performance in mainly draw call (CPU) bound scenarios (e.g. draw distance), and usually doesn't help much in GPU bound ones (e.g. resolution)
  
  • It is possible that DXVK won't change anything for you, or even make things worse
    
  
  
• Nvidia users on driver version >=520.56.06 and >=DXVK 2.0 will have a smoother experience thanks to a change in DXVK's caching system. AMD users can have the same benefit on driver version >=24.2.1 and DXVK >=2.4. This might not be supported in Intel GPU drivers (needs verification).
  
  
• DXVK's GPU compatibility varies between manufacturers
  
  • Nvidia GPU laptops must use the DXGI interop.
    Using it on desktops is not required, but highly recommended for the most optimal experience
    
    
  • AMD GPUs must use the DXGI interop, otherwise they will suffer from severe performance issues or fail to launch the game.
    Shader issues are more common on Windows compared to other GPUs (situation is completely reversed on Linux).
    
    
  • Intel GPUs from 6th Gen and newer can work provided you have newest drivers installed.
    On some iGPUs, DXVK is broken past the 1.10.1 version.
    
  
  
• Fallout New Vegas has some known shader issues or quirks. They are not guaranteed to happen (getting rarer with DXVK updates), but they can occur:
  
  • Transparency multisampling uses dithering - (Vulkan handles alpha to coverage differently than drivers)
    
    • If you are an AMD, RADV Linux user, you can disable this behavior by setting RADV_DEBUG=noatocdithering environment variable.
      
  • Blood decals can suffer from color overflow and turn white, fixed by Blood Decal Flashing Fix. This doesn't happen on the Nvidia D3D9 driver thanks to a patch.
    

Due to DXVK's nature it relies on shader cache, which is compiled during the first use of that shader.
Because of that you can experience increased short stutter at the beginning of your playthrough.
This is completely normal and will not reoccur after compilation has finished.

HDR Mod

HDR-Mod is a DXVK mod made by Lilium (aka EndlesslyFlowering) and Wall_SoGB with the intention of adding HDR functionality to D3D9 games. Effectively it does 2 major things:

• Allows to display the game in HDR (10 or 16 bit).
• Upgrades the precision with which the game calculates colors, greatly reducing banding - as long as you have a 10 bit display or better.
  
  

This allows for HDR output and eliminates color banding from the game.

DXVK doesn't perform any HDR tone mapping, so you need to use Pumbo's ReShade AutoHDR or Special K (Nvidia only) for that.

Known quirks and issues

• Any images produced by the game that were meant to be in 8 bit (screenshots, save images) are distorted due to lack of color conversion, this is purely visual and won't affect gameplay. Use HDR Save Image Patch and New Vegas Reloaded fix save images.
  For screenshots it's recommended to use Game Bar, Steam, or your tone mapping utility.