Say For the timeframe 2006 as per RSX, as a tech noob, i think it will be 90nm, at least 500mhz clk, it has to have a max TDP of 100w, it has to run games at 720p, it has to emulate GS, it probably is GS suped up, it has to have shaders from OGL, it has to saturate FlexIO optimally, it will have pure eDRAM, it will be used exclusively for 3D rendering, PS3 will have 512mb XDR and the Toshiba SCC for I/O, HDMI and such....these are the clues i can think up...from a tech noob...
GS specs from Wiki
Info on the SCC
http://news.zdnet.com/2100-9584_22-144207.html
GS specs from Wiki
# Graphics processing unit: "Graphics Synthesizer" clocked at 147 MHz
* Pixel pipelines: 16
* Video output resolution: variable from 256x224 to 1280x1024 pixels
* 4 MB (4 × 220 bytes) Embedded DRAM video memory bandwidth at 48 gigabytes per second (main system 32 MB can be dedicated into VRAM for off-screen materials)
o Texture buffer bandwidth: 9.6 GB/s
o Frame buffer bandwidth: 38.4 GB/s
* DRAM Bus width: 2560-bit (composed of three independent buses: 1024-bit write, 1024-bit read, 512-bit read/write)
* Pixel Configuration: RGB: Alpha:Z Buffer (24:8, 15:1 for RGB, 16, 24, or 32-bit Z buffer)
* Dedicated connection to: Main CPU and VU1
* Overall Pixel fillrate: 16x147 = 2.352 Gpixel/s (rounded to 2.4 Gpixel/s)
o Pixel fillrate: with no texture, flat shaded 2.4(75,000,000 32pixel raster triangles)
o Pixel fillrate: with 1 full texture(Diffuse Map), Gouraud shaded 1.2 (37,750,000 32-bit pixel raster triangles)
o Pixel fillrate: with 2 full textures(Diffuse map + specular or alpha or other), Gouraud shaded 0.6 (18,750,000 32-bit pixel raster triangles)
* GS effects: AAx2 (poly sorting required)[37], Bilinear, Trilinear, Multi-pass, Palletizing (4-bit = 6:1 ratio, 8-bit = 4:1)
* Multi-pass rendering ability
o Four passes = 300 Mpixel/s (300 Mpixels/s divided by 32 pixels = 9,375,000 triangles/s lost every four passes)[38]
Info on the SCC
http://news.zdnet.com/2100-9584_22-144207.html