Why it matters: PC games haven't been able to take advantage of SSDs the way PlayStation 5 and Xbox Series games have because the proper APIs to do so aren't yet in place. That's finally starting to change with recent releases from Sony and Nvidia.
With the release of a new ray tracing-enhanced mod for Portal, Nvidia has debuted RTX IO, the company's method of implementing GPU decompression to drastically shorten load times. Sony's Ratchet & Clank: Rift Apart will also support the technology when it launches later this month.
Nvidia initially unveiled RTX IO in late 2020 alongside Microsoft's DirectStorage but hadn't mentioned it since. The latter technology is how the Xbox Series consoles leverage their internal NVMe SSDs for ultra-fast load times, an advantage that debuted on Windows earlier this year with the release of Forspoken. Another part of the puzzle, however, is drivers that tell the GPU to take over compression work that traditionally went to the CPU, which Nvidia introduced through RTX IO.
As a demonstration of the technology, the company has released Portal: Prelude RTX, an expansion of the free ray-tracing mod Nvidia released for Portal late last year. It brings path tracing to a highly-regarded fan-made level pack for the original Portal while demonstrating how GPU-based decompression loads high-quality textures faster than CPU decompression, minimizing texture pop-in.
More efficient decompression can also decrease game install sizes, which have ballooned beyond 100GB for most recent major titles. Nvidia claims that RTX IO shrunk Portal: Prelude RTX's install size by 44 percent, from over 30 GB to around 20.
The company plans to include RTX IO in its RTX remix suite, which will eventually let modders add path tracing and enhanced textures to certain classic PC games. Early testing has delivered transformative results in titles like Half-Life 2, SWAT 4, Max Payne, Need for Speed Underground 2, and more.
Intel and AMD also have plugins for GPU decompression through DirectX and DirectStorage, but it's unclear whether they're compatible with Vulkan, which RTX IO fully supports. If not, then GPU decompression for Vulkan titles could be exclusive to RTX GPUs in the short term.
Because Portal: Prelude RTX is designed specifically for Nvidia's cards, AMD Radeon and Intel Arc owners must likely wait until the PC port of Ratchet & Clank: Rift Apart ships on July 26 to see the difference GPU decompression makes.
Developers Insomniac and Nixxes confirmed that DirectStoage 1.2 will help the new release emulate the original PS5 version's near-instantaneous level transitions on NVMe SSDs, SATA SSDs, and HDDs. Blizzard plans to implement DirectStorage in Diablo IV, likely including RTX IO and other GPU decompression methods.
