Franky
Ludwig van
Normalerweise sind Diskussionen PS2 gegen XBox ja ziemlich 'reißerisch'. Eine hochinteressante Darstellung habe ich in der us-ps2 NG gefunden und einfach mal reinkopiert. Gab es hier sicherlich von den Fakten schon öfter, aber lohnt sich trotzdem zu lesen finde ich:
I'm not doubting the tech.spec. of the Xbox, but at the end of the day,
it's a pretty linear system. Yes it has components that run faster. No
argument there. Consider however the difference between a 2GHz P4 and
a 1.4GHz Athlon. The Athlon smokes the P4 at just about everything,
doing general purpose computing.
Now take a look at the architecture of the PS2. It has 5 main processors,
with specialised instructions in most of them (we'll ignore the FPU :-)
It has 10 FMAC's in the Emotion engine (that's CPU, VU0 and VU1), each
of which can do a 32-bit floating point multiply,accumulate and add in a
single clock cycle. That's ~3,000,000,000 FMACs per second. That's a lot
of general-purpose FMAC's. They're not dedicated to fog, or T&L, but
to whatever the programmer wants to do with them.
The *key* difference about the PS2 though (I think) is that it's a
dataflow-design. There is no central CPU running the entire show - it
has 10 DMA channels, and the idea is to set up data flows from one
processor (CPU, VU0, VU1, GPU etc.) to another. Ultimately the GPU gets
a display list which it renders offscreen then flips every VSync.
Consider also that the amount of data flowing over the bus means that
uploading programs to the processors is trivial by comparison, which
lends itself to writing modules of code which operate on designated
data. Each of the processors has a scratchpad of internal RAM (some
is even shared between processors) so that all of this can happen in
stoccato bursts rather than contentious streams.
Once you get your head around the design of the machine, it makes a lot
of sense - basically you're rendering squillions of polygons with effects
applied to them. This *is* a dataflow problem. It makes a lot of sense
to have a dataflow architecture to solve the problem.
This different design is why people are saying the PS2 games will
get a lot better - there's a lot more potential and flexibility there
than in the competing systems.
Oh yeah, and the games are better too <grin>
I'm not doubting the tech.spec. of the Xbox, but at the end of the day,
it's a pretty linear system. Yes it has components that run faster. No
argument there. Consider however the difference between a 2GHz P4 and
a 1.4GHz Athlon. The Athlon smokes the P4 at just about everything,
doing general purpose computing.
Now take a look at the architecture of the PS2. It has 5 main processors,
with specialised instructions in most of them (we'll ignore the FPU :-)
It has 10 FMAC's in the Emotion engine (that's CPU, VU0 and VU1), each
of which can do a 32-bit floating point multiply,accumulate and add in a
single clock cycle. That's ~3,000,000,000 FMACs per second. That's a lot
of general-purpose FMAC's. They're not dedicated to fog, or T&L, but
to whatever the programmer wants to do with them.
The *key* difference about the PS2 though (I think) is that it's a
dataflow-design. There is no central CPU running the entire show - it
has 10 DMA channels, and the idea is to set up data flows from one
processor (CPU, VU0, VU1, GPU etc.) to another. Ultimately the GPU gets
a display list which it renders offscreen then flips every VSync.
Consider also that the amount of data flowing over the bus means that
uploading programs to the processors is trivial by comparison, which
lends itself to writing modules of code which operate on designated
data. Each of the processors has a scratchpad of internal RAM (some
is even shared between processors) so that all of this can happen in
stoccato bursts rather than contentious streams.
Once you get your head around the design of the machine, it makes a lot
of sense - basically you're rendering squillions of polygons with effects
applied to them. This *is* a dataflow problem. It makes a lot of sense
to have a dataflow architecture to solve the problem.
This different design is why people are saying the PS2 games will
get a lot better - there's a lot more potential and flexibility there
than in the competing systems.
Oh yeah, and the games are better too <grin>
)
ie xbox hat 733Mhz,die Emotion Engine nur 200Mhz,Xbox ist daher auch 3,5Mal so schnell wie die Playstation2.Das ist eben einfach Blödsinn!!
und der prozessor ist kein celeron, sondern ein modifizierter p3 .. (aber auch kein celeron)... und: wir hatten das thema cisc und risc zur genüge, ab dem p2 ist alles risc, was aber im endeffekt cisc ausgibt.. trotzdem arbeiten die cpus mit risc.