Comparison of Freescale iMX31's video core to previous-gen 3D game platforms

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Summary: the iMX31, although with a lower triangle and fillrate output, blows the PS2 and PSP out of the water due to multitexturing, blending, and advanced feature support. It is similar to the Dreamcast in performance, and falls behind the Gamecube.

iMX31 Playstation 2 Playstation Portable Dreamcast Gamecube
Design and clock speed PowerVR MBX Lite, 66mhz Vector engine on CPU, 300mhz

Graphics engine, 147mhz

Vector engine on CPU, 222mhz

Graphics engine, 166mhz

PowerVR2 CLX2, 100mhz Custom ATI design, "Flipper", 162mhz
Memory 32MB maximum, 32-bit 266mhz DDR system memory (iMX31 supports lesser memory as well), hardware texture compression supported 4MB, 147mhz (47GB/sec memory bandwidth), three independant busses of 1024, 1024, and 512 bits each, no texture compression 2MB, 166mhz, 512 bit bus, no texture compression 8MB with VQ compression (30MB-40MB worth of compressed textures), 100mhz, 64 bit bus 2MB frame buffer + 1MB texture cache storing 7MB worth of S3TC compressed textures (~8MB total), 162mhz (10.4GB/sec actual, 72.8GB/sec factoring in S3TC compression of 7x)
Draw rate in realistic million triangles per second (mtps)

fill rate in realistic million pixels per second (mpps)

0.9 mtps (double textures, bilinear filtering, gouraud shading), likey 2-5 times higher due to hidden surface detection (HSD)

100 mpps, more if HSD works well on scene

16 mtps (single texture, bilinear filtering, gouraud shading), 8 mtps (two textures), many games use more than two textures, no hardware texture compression even though many games use it

Note: NO HARDWARE MULTITEXTURING

100 mpps, far less than that when using many textures

12 mtps (single texture, bilinear filtering, gouraud shading), 6 mtps (two textures), many games use more than two textures, no hardware texture compression even though many games use it

Note: NO HARDWARE MULTITEXTURING

100 mpps, far less than that when using many textures

1 mtps, (double textures, bilinear filtering, gouraud shading), 2-5 times highr due to HSD

100 mpps, more if HSD works well on scene

12 mtps (double textures, bilinear filtering, gouraud shading)

648 mpps

Hardware acceleration features
  • Polygon setup
  • Flat and gouraud shading
  • Perspective-correct texturing
  • Specular highlights
  • Floating-point Z-buffer
  • 32-bit ARGB internal rendering
  • Per-vertex fog
  • ARGB 8888 textures, YUV 422 textures
  • PVR-TC compressed textures
  • Bilinear, Trilinear, Anistropic filtering
  • All OpenGL and D3D blend modes
  • Dot3 bump mapping
  • Alpha test
  • Zero-cost full-scene anti-aliasing
  • Polygon and NURBS setup
  • Bilinear filtering
  • Tesselllation
  • Vertex blending
  • Per-vertex fog
  • Depth and stencil tests
  • Almost all "features" quoted by Sony (not listed here) are done by reprogramming hardware
Same features as PS2, but no re-programmable pipeline, thus, no neat eyecandy effects done in hardware Similar feature set to iMX31 Similar feature set to iMX31
Resolution 800x480 7" LCD on Isaac 640x480i (TV maximum), 640x480p with VGA output 480x272 4.3" LCD 640x480p 640x480p