RSX Reality Synthesizer

This article is about the graphics chip. For RSX, see RSX (disambiguation).

The RSX Reality Synthesizer graphics processing unit is a graphics chip design co-developed by NVIDIA and Sony for the PlayStation 3 computer console.

Specifications

• 500 MHz G70 based GPU on 90 nm process
  • 300 million transistors total
  • Multi-way programmable parallel floating-point shader pipelines
    • Independent pixel/vertex shader architecture
    • 24 parallel pixel pipelines
      • 5 shader ALU operations per pipeline per cycle ( 2 vector4 and 2 scalar (dual/co-issue) and fog ALU )
      • 27 FLOPS per pipeline per cycle
    • 8 parallel vertex pipelines
      • 2 shader ALU operations per pipeline per cycle ( 1 vector4 and 1 scalar, dual issued )
      • 10 FLOPS per pipeline per cycle
    • Maximum vertex count: 1 billion vertices per second ( 8 vertex x 500 MHz / 4 )
      • Minimum (worst case) polygon count: 333.3 million polygons per second ( 1 billion vertices per second / 3 vertices per triangle)
      • Maximum (optimistic case) polygon count: 800 million and more depending on how many triangle strips are used in a game.
    • Maximum shader operations: 136 shader operations per second
    • Announced: 1.8 TFLOPS (trillion floating point operations per second)
    • GPU floating point performance 52 ALU ops * 4 floats per op *2 (madd) * 500 MHz = 228.8 GFLOPS.
  • 24 texture filtering units (TF) and 8 texture Addressing unit (TA)
    • 24 filtered samples per clock
      • Maximum texel fillrate: 12 gigatexel per second ( 24 textures x 500 MHz )
    • 32 unfiltered texture samples per clock ( 8 TA x 4 texture samples )
  • 8 Render Output units
    • Maximum pixel fillrate: 4 gigapixel per second ( 8 ROPs x 500 MHz )
    • Maximum Z sample rate: 8 gigasamples per second ( 2 Z samples x 8 ROPs x 500 MHz )
    • Maximum anti-aliasing sample rate: 8 gigasamples per second ( 2 AA samples x 8 ROPs x 500 MHz )
  • 74.8 billion shader operations per second
  • Maximum Dot product operations: 33 billion per second
  • 128-bit pixel precision offers rendering of scenes with high dynamic range rendering ( HDR)
  • 256 MiB GDDR3 RAM at 650 MHz
    • 128-bit memory bus width
    • 20.8 GiB/s read and write bandwidth
  • Cell FlexIO bus interface
    • 20 GiB/s read to the Cell and XDR memory
    • 15 GiB/s write to the Cell and XDR memory
  • Support for OpenGL ES 2.0
  • Support for DirectX 9.0c/API and Shader Model 3.0
  • Support for S3TC texture compression

Press Releases

Staff at Sony were quoted in Playstation Magazine saying that the "RSX shares a lot of inner workings with NVIDIA 7800 which is based on G70 architecture. Since the G70 is capable of carrying out 136 shader operations per clock cycle, the RSX was expected to feature the same number of parallel pixel and vertex shader pipelines as the G70, which contains 24 pixel and 8 vertex pipelines. The specs announced at the Tokyo Game Show in September 2006 confirmed this.

NVIDIA CEO Jen-Hsun Huang stated during Sony's pre-show press conference at E3 2005 that the RSX would be more powerful than two GeForce 6800 Ultra video cards combined.