I don't understand why you would want to run Linux on the PS3 anyway, besides just for funzies. It lacks RAM, no access to GPU, and doesn't the cell processor also run slow, and only let you access one core? Sounds like a terrible computing experience to me.
Correct me if I'm wrong, but each cell has all of the above components built in. They are all merged into 1 chip.
Sorry but you are wrong fohfoh.
The Cell microprocessor is actually 8 physical cores with 1 disabled.
To my understanding, 1 is used for general calculations while 6 are specialized cores for something or rather.
Putting the Cell CPU, RAM and GPU on one chip would make the PS3's price go up even further due to the immense cooling required and not provide much of a performance gain over upgrading the CPU or GPU.
edit: from wikipedia
"The PlayStation 3 uses the Sony, Toshiba, IBM-designed Cell microprocessor as its CPU, which is made up of one 3.2 GHz PowerPC-based "Power Processing Element" (PPE) and eight Synergistic Processing Elements (SPEs). The eighth SPE is disabled to improve chip yields. Only six of the seven SPEs are accessible to developers as the seventh SPE is reserved by the console's operating system. Graphics processing is handled by the NVIDIA RSX 'Reality Synthesizer', which can output resolutions from 480i/576i SD up to 1080p HD. The PlayStation 3 has 256 MB of XDR DRAM main memory and 256 MB of GDDR3 video memory for the RSX."
The Nvidia RSX 'Reality Synthesizer' is another name for 7800GTX.