Intel ARC GPUs, Xe Architecture for dGPUs [2022-]

[Man from Atlantis]

Here, I’ll be looking at a Cyberpunk 2077 frame rendered on Intel’s Arc B580, with path tracing enabled. As always, I’m focusing on how the architecture handles the workload, rather than absolute performance.

Raytracing workloads are diverse, and engineers have to allocate their transistor budget between fixed function BVH traversal hardware and regular vector execution units. It reminds me of DirectX 9 GPUs striking a balance between vertex and pixel shader core counts. More vertex shaders help with complex geometry. More pixel shaders help with higher resolutions. Similarly, BVH traversal hardware deals with geometry. Hit/miss shaders affect on-screen pixel colors, though they operate on a sample basis rather than directly calculating colors for specified pixel coordinates

Intel Arc B580 GPU, significantly improves ray tracing over its predecessor with upgraded RT Accelerators, increased BVH traversal pipelines (from 2 to 3), and doubled BVH cache (8 KB to 16 KB). These enhancements reduce memory latency and boost performance in complex workloads like Cyberpunk 2077's path tracing. With a stronger shader array, the B580 handles RT calculations more efficiently.

Raytracing on Intel’s Arc B580

Edit: The article originally said Intel’s BVH nodes were 4-wide, based on a misreading of QuadLeaf.

chipsandcheese.com

 

[trinibwoy]

Great article as always. Intel’s profiler is really impressive. It always saddens me to see the terrible utilization rates on GPU hardware. Makes you wonder why these companies keep spending so many transistors on compute when memory is almost always the bottleneck.

 

[Cyan]

Intel and Microsoft showcase AI-powered texture compression at GDC 2025 Neural rendering and neural shaders are here, and AI-powered Neural Block Texture Compression is one thing that will bring big performance gains.

At GDC 2025, Intel's Anis Benyoub is joining Microsoft on stage as it showcases 'Cooperative Vectors on DirectX,' a new feature that will lead to a 10X improvement in inference performance for Neural Block Texture Compression on Intel Arc GPUs. Joe Rozek from AMD and Alexey Panteleev from NVIDIA will also be there to discuss how Cooperative Vectors will be used with Radeon and GeForce RTX hardware.

As described by Intel, "Cooperative Vectors allow the multiplication of matrices with arbitrarily sized vectors to be run on any shader stage. Therefore, they can be used not only for training AI models, e.g., using compute shaders, but also for real-time inference, specifically per-pixel inference, to accelerate the execution of neural rendering techniques on hardware with AI acceleration." Translation, Cooperative Vectors allow AI models to run during all stages of the rendering process with direct access to game and on-screen data.

Intel's Arc hardware includes powerful XMX units for AI workloads; Cooperative Vectors will help pave the way for neural rendering and neural shaders to become an integral part of game development and how games run on modern GPUs. Intel isn't alone in supporting Neural Block Texture Compression as a way to reduce texture sizes without losing quality; AMD is also all in on the tech thanks to RDNA 4's beefy AI upgrade, while NVIDIA is also deeply invested in a range of RTX Neural Shaders aimed at improving performance and reducing the VRAM footprint of modern games.

 

[trinibwoy]

Great to see all 3 IHVs pushing forward together. Maybe we’ll actually see some results soon.