The original PlayStation 3 had 512 MB of total system memory. This was divided into 256 MB of XDR DRAM for the Cell processor and 256 MB of GDDR3 video memory for the RSX graphics processor.
The split architecture reflected the console’s unusual hardware design. The Cell Broadband Engine handled general processing through its Power Processing Element and Synergistic Processing Elements, while the RSX rendered graphics and used its dedicated memory pool.
This arrangement is easy to confuse with the amount of memory available to either processor individually. The console did not have 512 MB of one shared, uniform memory; it had two separate 256 MB pools.
Later PlayStation 3 revisions changed storage, size, power use, and exterior design, but the widely cited memory specification remained 256 MB of XDR plus 256 MB of GDDR3.