The Portal with RTX update added optional DLSS 5 Neural Rendering and other RTX Remix features, but no new levels or game content. The rollout was reported for October 21, 2026. NVIDIA describes the patch as a technical update to the existing demo in its official Steam notice.
What changed in Portal with RTX
Neural Rendering is off by default. The update also adds Frame Generation Preset C, 5X and 6X Multi Frame Generation for supported GPUs, Sparse Rendering, SHaRC, fixes for jagged self-shadowing, and support for compatible Windows on ARM systems.
NVIDIA representative Jacob Freeman posted a showcase of the Portal with RTX implementation on October 21.
How to turn on Neural Rendering
Install the update, launch Portal with RTX, then press Alt+X to open the RTX Remix settings. Enable Neural Rendering there if the option appears for your hardware and driver. It is optional and disabled by default.
Steam lists Portal with RTX as free DLC for owners of Portal on its store page.
DLSS 5 and Frame Generation have different hardware scopes
The update lists different hardware requirements for Neural Rendering and frame-generation modes. Support for one does not establish support for another.
| Feature | Role | Hardware scope stated |
| DLSS 5 Neural Rendering | Adds a neural-rendering stage to the image pipeline | NVIDIA’s general DLSS 5 description specifies one GeForce RTX 50 Series GPU |
| Frame Generation Preset C | A faster Performance Mode for Frame Generation | GeForce RTX 40 Series, GeForce RTX 50 Series, and RTX Spark laptops |
| 5X/6X Multi Frame Generation | Generates additional frames | Supported GeForce RTX 50 Series GPUs |
For DLSS 5, NVIDIA describes local processing on one GeForce RTX 50 Series GPU at resolutions up to 4K. The Portal with RTX notice says that available options depend on hardware and drivers. Its RTX 40 Series listing applies to Frame Generation Preset C, not to DLSS 5 Neural Rendering.
Where DLSS 5 fits in rendering
DLSS 5 is a final neural-rendering stage. NVIDIA says it uses the engine-rendered frame, frame color, motion vectors, and scene information such as artist-authored geometry, textures, and lighting buffers. The process takes one frame in and produces one frame out. It is distinct from Frame Generation, which creates additional frames. NVIDIA explains the general approach in its DLSS 5 developer overview.
The other rendering changes target specific parts of the pipeline. Sparse Rendering calculates fewer lighting samples and uses DLSS Ray Reconstruction to reconstruct the image. SHaRC, or Spatially Hashed Radiance Cache, is an indirect-lighting cache option alongside Neural Radiance Cache. The shadow fixes reduce jagged self-shadowing on curved and low-polygon surfaces.
NeoTeo’s earlier DLSS 5 coverage of NBA 2K27 reports measurements for that game. Those results are specific to NBA 2K27, not Portal with RTX.
Half-Life 2 RTX Demo received a separate update
On October 23, 2026, Jacob Freeman announced a separate update to the Half-Life 2 RTX Demo. That update concerned the demo, not the full remaster.
