Nvidia adds DLSS 3, raytracing, and RTX IO in this free update to a Portal mod.
Called Portal: Prelude RTX, it’s free for owners of the original Portal on Steam once it’s released at 3PM ET today. This is the first title to use Nvidia’s RTX IO, which supports both DirectStorage and Vulkan, using GPU cores to load compressed data directly from storage to the graphics card. The system is also being used in the PC port for Ratchet & Clank: A Rift Apart. Portal Prelude is unrelated to the similarly-named side-scroller for graphing calculators.
Source: theverge.com