Hello!

Thank you so much for your interest in the free Portal with RTX DLC. :)

Please see below for some frequently asked questions, and note that Portal with RTX implements full ray tracing, so please check recommended System Requirements [images.nvidia.com]

How do I adjust & optimize the Portal with RTX graphics settings?
Please use Alt-X to open the Remix graphics window and adjust settings from there. Please do not alter the native Portal settings as this may cause instability, instead use Alt-X.

https://gtm.steamproxy.vip/games/2012840/announcements/detail/3620361554187542942

What are the minimum recommended specifications for Portal with RTX?
A VulkanRT capable graphics card is required for Portal with RTX. Portal with RTX is best experienced on RTX 40 Series GPUs with DLSS 3. We highly recommend you view the recommended system requirements.

Recommended System Requirements [images.nvidia.com]

Where can I get more information about Portal with RTX?
Portal with RTX GeForce Launch Article[www.nvidia.com]

Where can I report or find info on common tech issues?
https://gtm.steamproxy.vip/app/2012840/discussions/0/3726197342900188299/

Who is the developer for Portal with RTX?
The developer of Portal with RTX is NVIDIA Lightspeed Studios.

Who is the publisher for Portal with RTX?
The DLC was created entirely by NVIDIA, while we worked in association with Valve.

Did you add any new content or levels to Portal?
No, we wanted to keep gameplay as close to the original as we could. This is the original version of the game, with modified textures, meshes, path-traced lighting, and DLSS 3.

How much is Portal with RTX?
Portal with RTX is a free download on Steam if you already own the game.

Do I need to own Portal to play Portal with RTX?
Yes, Portal with RTX is a free download for owners of the base Portal game.

What is full ray tracing and how is it used in Portal with RTX?
Portal with RTX is enhanced with full ray tracing, an advanced, GPU-intensive (see recommended & minimum specs here), version of ray tracing referred to as “path tracing” which unifies all lighting effects such as shadows, reflections, global illumination, refractions and more into a single algorithm. Enjoy Portal’s famous test chambers with every photon of light fully ray traced in real time!

Experience realistic lights that bounce off of every surface, and cast reflections on every object, from the iconic portal gun to the warped glass that lines every chamber in the Aperture Science Enrichment Center. Light even shines through portals!

Does Portal with RTX only work on NVIDIA GPUs?
Portal with RTX uses Vulkan ray tracing and should run on any VulkanRT capable graphics card. FPS may struggle on non-RTX hardware without RT Cores and DLSS though. Portal with RTX is best experienced on RTX 40 Series GPUs with DLSS 3.

What graphics tech has been added to Portal with RTX?
New graphics techniques used in Portal with RTX include:

• Full ray tracing - Portal with RTX uses a ray tracing technique known as path tracing or full ray tracing, which unifies all lighting effects, such as shadows, reflections, refractions and more, into a single ray tracing algorithm.
  
• NVIDIA DLSS 3– DLSS 3 is a revolutionary breakthrough in neural graphics that massively boosts performance. Powered by fourth generation Tensor Cores and new Optical Flow Accelerator on GeForce RTX 40 Series GPUs, DLSS 3 uses AI to generate additional high-quality frames with great image quality and responsiveness.
  
• NVIDIA Reflex - Improves responsiveness by reducing end to end system latency, enabling players to feel more connected and immersed in the experience.
  
• NVIDIA Real Time Denoisers (NRD) is a new spatio-temporal ray tracing denoising library that assists in denoising ray traced images in real-time, with superior performance and quality.
  
  Next-Generation Ray Tracing Features:
  
• Shader Execution Reordering (SER) - improves ray tracing performance by sorting traced rays, making them more coherent and therefore more efficient to execute on GPUs.
  
• Opacity Micromap (OMM) - speeds up ray tracing performance of non-fully opaque surfaces by encoding surface transparency data into a ray tracing acceleration structure and enabling a more efficient ray surface resolve on GPUs.
  
  A new lighting system made possible by NVIDIA RTXDI, NVIDIA ReSTIR GI and the addition of physically based materials/rendering (PBR):
  
  
• NVIDIA RTX Direct Illumination (RTXDI) enables the addition of countless direct light sources, big and small, each casting light and shadows.
  
• NVIDIA Reservoir Spatio Temporal Importance Resampling Global Illumination (ReSTIR GI) enhances indirect light, enabling it to bathe a scene and illuminate dark corners that are not lit directly. And it also works smarter than previous ray-traced global illumination techniques, improving the efficiency of our ray tracing denoiser.
  
• Physically based materials/rendering (PBR) – the environment of Portal’s Aperture Labs is upgraded with material properties that emulate real life. This PBR system supports material properties for light emission, roughness, and metallicity that combine with ray tracing to enable lighting effects such as reflections, refraction, translucency, transparency and global illumination.
  
• More detailed models – in-game objects have been remodeled to add more detail and increase realism.

What are Physically-based rendering (PBR) textures?
The materials in Portal with RTX are now upgraded with material properties that emulate real life — a technique known as physically based rendering (PBR). This PBR system supports material properties for light emission, roughness, depth and metallicity that combine with ray tracing to enable lighting effects such as reflections, refraction, translucency, transparency and global illumination that open new possibilities such as mirror and glowing lava blocks in Portal with RTX.

How does ray tracing affect current Portal mods?
Based on limited testing so far, we expect Portal with RTX to be compatible with most existing Portal mods.

Does Portal with RTX use any rasterization?
Portal with RTX is fully ray traced aside from the UI.

What version of NVIDIA DLSS is in Portal with RTX?
Portal with RTX supports DLSS 3 which includes DLSS Super Resolution, as known as DLSS 2


https://youtu.be/ms1W3TD9de0


https://www.youtube.com/watch?v=DwFCSsc99Rk