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Is the new DirectX Raytracing update going to make ray tracing cheaper on your GPU? Eventually, maybe. On October 28, Microsoft released a preview of what it calls the most significant update to DirectX Raytracing (DXR) since its debut in 2018. It adds two features, Clustered Geometry and Partitioned Top-Level Acceleration Structures (PTLAS), designed to make detailed, animated ray-traced scenes much cheaper to update. VideoCardz, TechPowerUp and heise online all covered the release.
Did the GPU makers respond? Yes. Microsoft's DirectX Developer Blog post includes statements from NVIDIA, AMD, Intel and Qualcomm, and all four say they are supporting the features. The catch: this is a developer preview, not a setting you can turn on in today's games.
What does the DirectX Raytracing update actually change?
Ray tracing relies on acceleration structures, data that organizes a scene's geometry so the GPU can quickly work out what each ray hits. When objects move, animate or stream in, those structures have to be rebuilt, and in large, detailed worlds that gets expensive.
- Clustered Geometry splits models into small reusable clusters of up to 256 triangles and 256 vertices. Instead of rebuilding a whole object, an engine can reuse clusters or rebuild only the ones that changed. Microsoft says this can make it practical to ray trace the same full-detail geometry used for normal rendering, so ray-traced shadows and reflections match what you actually see.
- Partitioned TLAS applies the same idea to the whole scene, so the update cost follows what changed rather than the entire world.
- GPU-driven builds let the GPU generate and run these build operations itself, instead of waiting on the CPU to describe each one.
Microsoft says the features don't require new ray tracing hardware. Whether a given GPU gets them depends on each vendor writing and validating drivers.
Is the 90% memory saving real?
In one test, yes, but read the fine print. Microsoft ran its Clustered Geometry sample on an AMD Radeon RX 9070. Compared with traditional rebuilds:
- Frame rate went from 1.2 FPS to 79 FPS, about 66 times higher.
- Per-frame acceleration structure build time dropped from 788 ms to 3.11 ms.
- Total acceleration structure memory fell from 7,519 MiB to 774 MiB, or 89.7% less.
Microsoft itself warns, in capital letters, not to assume games will see wins of this size, because the sample is a test playground. heise online points out that the figure only covers ray tracing acceleration structures, not the textures and other data that fill your VRAM, and Microsoft's own table shows the new method needs more temporary scratch memory during builds. TechPowerUp's view is that real games should generally see gains of a few percent.
Which GPUs support Clustered Geometry and PTLAS?
Here is Microsoft's list of currently supported hardware:
- NVIDIA: all GeForce RTX GPUs. NVIDIA's Martin Stich says the company is "excited to fully support this update to DXR on all RTX GPUs."
- AMD: Radeon RX 9000 series, with a dedicated preview driver.
- Intel: Arc B-Series graphics and Core Ultra 200V and Series 3 processors.
- Qualcomm: Snapdragon X2 platforms, with driver support targeted for Q1 or Q2 2027.
Support for some older ray tracing GPUs is "to be determined," Microsoft says, because driver work may uncover performance issues. That means Radeon RX 7000 and RX 6000 cards and Intel Arc A-Series aren't on the list for now.
When will games use the new DirectX Raytracing features?
There's no date yet. The features ship in the DirectX 12 Agility SDK 1.722 preview with Shader Model 6.10, and developers need a supporting driver plus Windows Developer Mode to enable them. Microsoft hasn't said when they'll reach a retail release. One early sign: Gears of War: E-Day already uses clustered geometry through NVIDIA's own RTX Mega Geometry API, and Microsoft says standardizing it in DirectX gives future games a common path across GPU brands.
Buy or wait: should this change your GPU plans?
Don't upgrade for this alone. It's a developer preview, and any benefit depends on game studios adopting it over the coming months and years. What it does show is where ray tracing is heading: detailed, animated open worlds where memory and update costs matter. If you're shopping now and ray tracing is a priority, a card already on the supported list, such as a GeForce RTX model or a Radeon RX 9000, is a safer bet than an older generation whose support is still undecided. Browse our graphics cards, or skip the parts hunt with a ready-to-play gaming PC. On a tighter budget, our refurbished PCs are worth a look.
FAQ
Is the DirectX Raytracing update available in games now?
No. It's an experimental developer preview in Agility SDK 1.722, and Microsoft hasn't given a retail date.
Will it cut my VRAM use by 90%?
Unlikely. The 89.7% figure comes from one Microsoft test scene on an RX 9070 and only covers acceleration structure memory. Microsoft warns that games won't necessarily see wins that large.
Does my RTX 20 or RTX 30 card support it?
Yes, according to NVIDIA, which says it supports the update on all RTX GPUs.
Do I need a new GPU for Clustered Geometry?
Not necessarily. Microsoft says it doesn't require new hardware features, but support depends on drivers, and some older ray tracing GPUs are still to be determined.
Sources: Microsoft DirectX Developer Blog, Agility SDK release notes, VideoCardz, TechPowerUp, heise online. Image credit: Microsoft / NVIDIA.
