Portal: Prelude RTX is a stunning fully ray-traced remaster of the iconic prequel mod for Portal, featuring NVIDIA DLSS 3 and RTX IO. Survive a facility run by Aperture Science's heartless employees in 19 challenging new chambers and learn how everything came crashing down.
Recent Reviews:
Mixed (46) - 43% of the 46 user reviews in the last 30 days are positive.
All Reviews:
Mixed (1,226) - 40% of the 1,226 user reviews for this game are positive.
Release Date:
Jul 18, 2023

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Community-Made Mod

This community-made mod requires that you own Portal.

Click here to learn more about mods on Steam.

Install Portal: Prelude RTX



“The best thing to happen to Portal since its release!”
Canard PC (FR)

“Make no mistake, after all the hype, this mod is no lie.”

“A extensive work of love with an excellent result.”
Joystick Magazine

About This Game

Portal: Prelude RTX is a free mod for all Portal owners.

In partnership with NVIDIA and powered by RTX Remix, Portal: Prelude RTX is a remaster of the 2008 ModDB Mod of the Year Top 3 Winner, Portal: Prelude, with stunning full ray tracing and high-fidelity assets, the groundbreaking AI-accelerated performance of DLSS 3, and the lowest texture load times with RTX IO. Step into the boots of Abby, the newest testing associate in Aperture Science, as you solve nineteen mind-bending chambers putting your Portal skills to the ultimate test. Make use of momentum, perform narrow escapes through deadly particle fields, and learn to work with manipulated gravity while heartless but dedicated observers watch and berate your every move.

When you finally come face to face with the minds behind Aperture Science, witness the scientific hubris marking the downfall of the facility as the activation of GlaDOS sets the scene for the rest of the Portal series to follow.

Portal: Prelude RTX features

  • Nineteen challenging new test chambers, many improved from the original mod's release.
  • A total graphical overhaul of the game's lighting and assets, powered by RTX Remix in partnership with NVIDIA.
  • A cast of several fully-voice acted characters compared to the robotic voices of the original.
  • A dramatic origin story for one of the most iconic villains and settings in gaming.
  • An experience created by modders, helmed by modders, and released for fans of Portal to test their mettle.

System Requirements

    • OS: 64-bit Windows 10 / Windows 11
    • Processor: Intel i7-6700, AMD Ryzen 5 3600
    • Memory: 16 GB RAM
    • Graphics: NVIDIA GeForce RTX 2060
    • Storage: 25 GB available space
    • OS: 64-bit Windows 10 / Windows 11
    • Processor: Intel i7-9700K, AMD Ryzen 5 3600
    • Memory: 16 GB RAM
    • Graphics: NVIDIA GeForce RTX 3080
    • Storage: 25 GB available space

What Curators Say

8 Curators have reviewed this product. Click here to see them.

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