cisc vs risc

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MS

A few years ago we had the RISC processors. Used by apple and sun. These
processors used to be more powerful at the time than the Cisc tech.
What happened to risc cpu's?

MS
 
MS said:
A few years ago we had the RISC processors. Used by apple and sun. These
processors used to be more powerful at the time than the Cisc tech.
What happened to risc cpu's?

MS
Click to expand...
Lack of development??
 
What happened to risc cpu's?

http://en.wikipedia.org/wiki/Risc#Later_RISC
Today the vast majority of all 32-bit CPUs in use are RISC CPUs, and
microcontrollers. RISC design techniques offers power in even small sizes,
and thus has become dominant for low-power 32-bit CPUs. Embedded systems are
by far the largest market for processors: while a family may own one or two
PCs, their car(s), cell phones, and other devices may contain a total of
dozens of embedded processors. RISC had also completely taken over the
market for larger workstations for much of the 90s (until taken back by
inexpensive PC-based solutions). After the release of the Sun SPARCstation
the other vendors rushed to compete with RISC based solutions of their own.
The high-end server market today is almost completely RISC based[citation
needed], and the #1 spot among supercomputers as of 2008[update] is held by
IBM's Roadrunner system, which uses Power Architecture-based Cell
processors[10] to provide most of its computing power, although many other
supercomputers use x86 CISC processors instead.

--g
 
Today the vast majority of all 32-bit CPUs in use are RISC CPUs, and
microcontrollers. RISC design techniques offers power in even small sizes,
and thus has become dominant for low-power 32-bit CPUs. Embedded systems are
Click to expand...

Intel and AMD are CISC?

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* MS:
A few years ago we had the RISC processors. Used by apple and sun. These
processors used to be more powerful at the time than the Cisc tech.
What happened to risc cpu's?
Click to expand...

Well, at the times you are talking about there was a more clear
distinction what RISC (Reduced Instruction Set Computing) and CISC
(Complex Instruction Set Computing) is. A lot has changed.

First, RISC processors got more complicated over time, with more
complicated instruction sets. On the other side, x86 became more
RISC-like with the Pentium and later processors. Today the complexity of
x86 and most "RISC" processors is quite similar.

Second, traditional RISC platforms (SUN SPARC, IBM POWER/PowerPC, SGI
MIPS, HP PA-RISC) have been declining for the last decade. The reason is
that while x86 was slow and limited say 15 years from today it did
benefit from faster development and lower costs, outperforming
traditional RISC in more and more areas. Today the traditional RISC
workstations from Sun, SGI and HP are gone, Apple also has abandoned the
PowerPC in favour of the faster intel Core. HP killed PA-RISC in favour
of IA64 (Itanium) which also is declining. MIPS and PowerPC are now
mostly used in the Embedded market, and IBM POWER and Sun SPARC are left
with the high end server/mainframe market, something which sooner or
later also will be overtaken from x86.

Benjamin
 
* MS:

Well, at the times you are talking about there was a more clear
distinction what RISC (Reduced Instruction Set Computing) and CISC
(Complex Instruction Set Computing) is. A lot has changed.

First, RISC processors got more complicated over time, with more
complicated instruction sets. On the other side, x86 became more
RISC-like with the Pentium and later processors. Today the complexity of
x86 and most "RISC" processors is quite similar.

Second, traditional RISC platforms (SUN SPARC, IBM POWER/PowerPC, SGI
MIPS, HP PA-RISC) have been declining for the last decade. The reason is
that while x86 was slow and limited say 15 years from today it did
benefit from faster development and lower costs, outperforming
traditional RISC in more and more areas. Today the traditional RISC
workstations from Sun, SGI and HP are gone, Apple also has abandoned the
PowerPC in favour of the faster intel Core. HP killed PA-RISC in favour
of IA64 (Itanium) which also is declining. MIPS and PowerPC are now
mostly used in the Embedded market, and IBM POWER and Sun SPARC are left
with the high end server/mainframe market, something which sooner or
later also will be overtaken from x86.
Click to expand...

If I'm not mistaken, isn't the cell chip/processor found in the
Playstation 3 supposed to be RISC, as well as multi-core?
 
* Peter:
If I'm not mistaken, isn't the cell chip/processor found in the
Playstation 3 supposed to be RISC, as well as multi-core?
Click to expand...

Yes, the PS3 as the XBox uses a "RISC" CPU, both are PowerPC based. But
while the Xenon is a common symmetric multicore (like AMD Phenom or
intel Core 2) the Cell is a asymmetric processor (one general purpose
processing core and multiple special purpose coprocessor elements).

But these processors are not more "RISC" than Phenom or intel Core 2.

Benjamin
 
A few years ago we had the RISC processors. Used by apple and sun. These
processors used to be more powerful at the time than the Cisc tech.
What happened to risc cpu's?

MS
Click to expand...

Whatever else it isn't (what it is), an emphasis on pragmatics will
outweigh all else -- the loss of latent benefits, ie Microsoft
antitrust trust settlements at some divergence from being (what is not
IBM) dedicated to a garage/cottage industry of residential computer
tinkerers, as well, within an established framework of the business of
revolution known for the Personal Computer phenomena.

Let me see if I can "spit" that any better... A premise DOS
superceded, as it does *NIX variants, by in large analogous, while
within a purvey of [X]XX86 instruction sets, no less biased to
programs of old, as they are to the present;- whether that is from a
computer architect's standpoint debilitating, is an argument less
persuasive, than any affect substantially at variance from said
pragmatics, when push comes to play (while not shove) upon a matrix
indeed being implemented.

Hm... perhaps a little less discrete datum from Stanford's computer
dept., although I do not know that it does, in fact, affect an
outcome: RISC pragmatically once assayed from predominately AMD and
the home PC owner. Or, perhaps, I'm simply no less ignorant, as
apparently your are, of greater CISC factors seen as a motivational
impetus behind business modeling, then to impart a significance in the
presence of "state of the art" multicore platforms...

CISC / RISC

Emphasis on hardware /
Emphasis on software

Includes multi-clock complex instructions /
Single-clock, reduced instruction only

Memory-to-memory: "LOAD" and "STORE" incorporated in instructions /
Register to register: "LOAD" and "STORE" are independent instructions

Small code sizes, high cycles per second /
Low cycles per second, large code sizes

Transistors used for storing complex instructions /
Spends more transistors on memory registers
 
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