NVIDIA RTX Remix 1.5 released with RTX IO packaging, Smooth Normals and AI workflow files
Portal with RTX now takes 17GB instead of 25GB.

NVIDIA has released RTX Remix 1.5, the latest update to its modding platform for remastering older PC games with path tracing and updated assets. The update is available through GitHub and the NVIDIA App.
The main change in this release is the new RTX IO packaging workflow. RTX IO is NVIDIA’s storage technology for faster asset streaming, lower CPU overhead and smaller install sizes. RTX Remix 1.5 adds new RTX IO compression options, including split-size presets from 1GB to 16GB.
NVIDIA says Portal with RTX, Portal: Prelude RTX and the Half-Life 2 RTX demo have now officially integrated RTX IO. The company also confirmed lower file sizes for two of those projects.
RTX IO is our high-performance storage technology that speeds up game loading and reduces CPU overhead. It allows games to better stream high-quality textures while you move around the world, and reduces install sizes. RTX Remix 1.5 includes new RTX IO compression options in the packaging workflow, including split-size presets from 1GB to 16GB.
Portal with RTX, Portal: Prelude RTX, and the Half-Life 2 RTX demo have officially integrated RTX IO. Thanks to this update, file sizes have dropped significantly: Portal with RTX has been reduced from 25 GB to 17 GB, while Half-Life 2 RTX has shrunk from 80 GB to 50 GB.
Source: NVIDIA
Modded games can now be smaller
Portal with RTX has been reduced from 25GB to 17GB. That is around 32% smaller than before. The Half-Life 2 RTX demo has been reduced from 80GB to 50GB, which is a 37.5% reduction.
Portal: Prelude RTX is also listed as an RTX IO-supported project, although NVIDIA did not provide a new file-size figure for that release. The change should be useful for RTX Remix projects, which often include larger texture packs and path-traced lighting data.
Source: NVIDIA
RTX Remix 1.5 also adds Smooth Normals for captured legacy geometry, revised viewport light controls and new RTX Remix Skills for AI coding agents.
Source: NVIDIA