Why no more than 32-bit?

[GR1EVER]

Game systems like ps2 have high bit processors, like 128-bit. If that's better than most computers' processors (32-bit and some 64-bit) then why aren't computers made with higher bit-age? (is that a word?)

would that not yield sweeter computers?

 

[edfair]

Requires more real estate to make a general purpose CPU than a special purpose CPU. Requires more registers, more I/O, and more interconnects and generates more heat. But have faith, the 64s are coming.
May be a while for 128s.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[dakota81]

The ps2 uses a VLIW processor (very large instruction word) which is I believe 4 instructions of 32bits each. That's where the 128bit comes from. Most of that space is wasted, though, as software is inherintly sequential and it's actually quite difficult to find three instructions that can be executed in parallel, let alone 4!

Backwards compatibility is very difficult too on a VLIW processor; in contrast, intel's P4 really can execute any code written for the original 8086 twenty years ago, even though the cpu architecture has drastically changed since then. Twenty years from now I can guarantee absolutely no hardware support for ps1 or ps2 software in the new processors.

And VLIW processors cannot interact with complex memory systems. Cache memory causes design problems, and you can just forget about a virtual memory system that all major computers rely on.

So really, there's much much more to look at than just how many bits a processor is labelled as.

 

[BitFuzzy]

if you want 128bit processing, and have a ps2, you can always purchase the Linux conversion kit from Sony

 

[ANFPS26]

"ps2"? Is he talking "Play Station 2" or IBM PS2??

Jim

 

[BitFuzzy]

play station 2 (I'm assuming)

 

[Blujacket]

Must be the Play Station. IBM PS/1 and PS/2 computers go back several/many years.

 

[ANFPS26]

That's why I added the smiley face. I was trying to be funny.

Jim

 

[dakota81]

Looked it up; the ps2 is a two-wide VLIW processor, so each instruction is 64bit & the system can load 2 at a time in parallel.

 

[eggbtr]

Because Intel does not want the world to have a 64 bit processor, because it has a happy little monopoly and it likes the status quo. Microsoft didnt want to develop a 64 Bit Operating System, because it is working on Longhorn which is not going well. Motherboard manufacturers are working on PCI Express. All the present games will run plenty well with a 3 Gig Processor and a good video card.

 

[cdogg]

GR1EVER,
The 128-bit label can be a bit deceiving unless you know what you are comparing. The PS2 CPU is actually inferior to modern video cards which have GPU's that can operate at 256-bit. In a PC, the job is split up between the CPU and GPU, with the GPU doing most of the work. The Xbox uses a similar setup and actually has 128-bit access to memory.

In terms of graphics, GPU's are far more advanced than CPU's. That is because they're more specialized. A CPU, on the other hand, is running on a 32-bit OS and normally only processes code at 16 or 32-bit. It is an apples-to-oranges comparison to pit a GPU against a CPU. Besides, that same PS2 processor is only running at 300MHz, far slower than what you would expect to buy on the PC today.

~cdogg
[tab]"All paid jobs absorb and degrade the mind"
[tab][tab]- Aristotle

 

[GR1EVER]

Thank you for clearing that up, i guess.

I have a basic knowledge of computer architecture but not enough to really fully comprehend what you guys were talking about, but I think i got the basic "jist" of it.

 

[cdogg]

Well in short, the PS2 processor should be compared to a modern video card's processor (GPU), not a PC's processor (CPU) to get the apples-to-apples comparison. In that comparison, the PS2 loses in every aspect.