Memory
Four mebibytes of DRAM on the Graphics Synthesizer die, holding the frame buffer, Z buffer and textures behind a 2560 bit bus.
| Metric | Value | Evidence | Basis | Method | Source |
|---|---|---|---|---|---|
| Memory capacity memory | 4 MiB | Confirmed | Vendor-rated | Design capacity Stated by the vendor Embedded DRAM on the Graphics Synthesizer die, holding the frame buffer, the Z buffer and textures in one address space. The release writes "4MB", meaning 4 MiB. The figure is quoted from the 2003 description of the merged Emotion Engine and Graphics Synthesizer chip; the embedded memory was not resized when the two dies were combined. | |
| Memory bandwidth memory | 48 GB/s | Confirmed | Theoretical | Theoretical peak Stated by the vendor Peak transfer rate of the Graphics Synthesizer's embedded DRAM across its 2560 bit bus at 150 MHz. A bus maximum. The 2560 bit are not one bus but three ports — separate read and write paths for the frame and Z buffers plus a texture path — so no single operation can consume the whole figure. | |
| Memory bus width memory | 2560 bit | Confirmed | Vendor-rated | Design capacity Stated by the vendor The total width of the ports into the embedded DRAM, summed. It is an on-die figure and has no counterpart on a console whose graphics memory is external. |
70×
a ÷ b ratio v1 Compares memory-bandwidth at memory scope, obtained by theoretical-peak. Valid only within this comparability group, and reported to 2 significant digits — the precision of the least precise input. At least one input is a theoretical peak, which is an upper bound rather than an achieved result.
15×
a ÷ b ratio v1 Compares memory-bandwidth at memory scope, obtained by theoretical-peak. Valid only within this comparability group, and reported to 2 significant digits — the precision of the least precise input. At least one input is a theoretical peak, which is an upper bound rather than an achieved result.
The capacity and the bandwidth are the two halves of the same design decision. Putting the frame buffer on the die bought a bus no external memory of the era could match, and cost the console the room to hold large textures — which is why PlayStation 2 titles stream texture data from main memory during drawing.