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Sony Says Nobody Will Ever Use All the Power of a PS3
Tighthead Prop writes "Sony executive Phil Harrison has made some brash comments about the Cell processor and the PlayStation 3. Harrison says that the current PS3 game lineup is using less than half of the machines power, adding that 'nobody will ever use 100 percent of its capacity.' Is he right? 'The major reason Harrison wants to hype up the "unlimited" potential of the PS3's architecture is to downplay comparisons between games running on Sony's console and Microsoft's Xbox 360. The two systems are not completely dissimilar: they both contain a PowerPC core running at 3.2 GHz, both have similarly-clocked GPUs, and both come with 512 MB of RAM.'"
Ubisoft says Assassins Creed will have more intelligent AI in the 360 version simply because the three dedicated cores offer more raw horsepower that the PS3 doesn't have. You can also tell that the PS3 has run into some issues regarding the limit of 256MB of texture memory compared to the 360, most textures are all blurry and low res compared to their 360 counterparts. It's the PS2 hype all over again.
Having said that, for such a nerd-oriented site, I can't believe some of the parsing going on here, and it must come down at least partially to latent Sony-hate (for whatever reason).
Let's just put the word 'Sony' aside, for ONE second. Just bear with me here.
The PS3's 3.2 GHz Cell processor, developed jointly by Sony, Toshiba and IBM ("STI"), is an implementation to dynamically assign physical processor cores to do different types of work independently. It has a PowerPC-based "Power Processing Element" (PPE) and six accessible 3.2 GHz Synergistic Processing Elements (SPEs), a seventh runs in a special mode and is dedicated to OS security, and an eighth disabled to improve production yields. The PPE, SPE's and other elements ("units") are connected via an Element Interconnect Bus which serves to connect all of the units in a ring-style bus. The PPE has a 512 KiB level 2 cache and one VMX vector unit. Each SPE is a RISC processor with 128 128-bit SIMD GPRs and superscalar functions. Each SPE contains 256 KiB of non-cached memory (local storage, "LS") that is shared by program code and work data. SPEs may access more data in the main memory using DMA. The floating point performance of the whole system (CPU + GPU) is reported to be 2 TFLOPS[74]. PlayStation 3's Cell CPU achieves 204 GFLOPS single precision float and 15 GFLOPS double precision. The PS3 will ship with 256 MiB of Rambus XDR DRAM, clocked at CPU die speed.
That is one deeply weird hunk of hardware. And its pretty fucking cool. Or at least, IBM seems to think so.
Someone has tried to dumb down an explanation like this to our boy Phil and he shat out this 'will never use the full potential' idiocy, which in turn riles all the nerds because its just such a lame thing to say, you can poke holes in it all day (such as, 'why build such a complicated beast if we will never be able to program it - equally idiotic).
So the statement is 100% true, and 100% meaningless.
Like the hamburger truck at the end of my street that claims Greatest Burgers in the Universe.
If Jesus wants me it knows where to find me.
The amount of RAM is a different issue from being bottlenecked on the memory subsystem. Long ago a cpu running 1mhz had memory running at the same rate - you could effectively manage a memory access per instruction. Over time CPUs got faster faster than memory got faster. So caches showed up to try to mask it. On a PS2 a cache miss wound up costing 40-60 cycles. Ouch. And the trend has continued, but now it's worse: on the PS3 a cache miss is something ludicrous like 400-600 cycles. Think of it: 500 instructions possible in the time it takes to fetch from memory. Without getting clever, you wind up spending a lot of time stalled waiting for memory. And that's without piles of contention from lots of different threads and processors trying to use the same bus. That's what's meant by being bottlenecked on memory.