CPU v/s GPU

R

RC

This may seem like a stupid question, but what is the difference
between a CPU and a GPU.
I know one does graphics and makes it possible to play games or use
software they couldn't without one.
But, really, what it is processing is numbers, so why is one better at
certain tasks?
In the past, a CPU did both functions, but now it can't keep up.
Even a duel core computer can benefit from a GPU. So it would seem a
GPU can do more then a CPU. (Maybe maybe not.)
But if it can, why not use them as a CPU.
Or instead of a quad core system, why not a system with 2 CPUs and 2
GPUs on the MB. I mean real GPUs no the BS they try to pass off as
GPUS - GPUs that may let you play such cutting edge games as Commander
Keen, or the SOD series.

Yes, I have little understanding in this area and would be most
appreciative if someone could help me sort it all out.

RC
 
P

Paul

RC said:
This may seem like a stupid question, but what is the difference
between a CPU and a GPU.
I know one does graphics and makes it possible to play games or use
software they couldn't without one.
But, really, what it is processing is numbers, so why is one better at
certain tasks?
In the past, a CPU did both functions, but now it can't keep up.
Even a duel core computer can benefit from a GPU. So it would seem a
GPU can do more then a CPU. (Maybe maybe not.)
But if it can, why not use them as a CPU.
Or instead of a quad core system, why not a system with 2 CPUs and 2
GPUs on the MB. I mean real GPUs no the BS they try to pass off as
GPUS - GPUs that may let you play such cutting edge games as Commander
Keen, or the SOD series.

Yes, I have little understanding in this area and would be most
appreciative if someone could help me sort it all out.

RC

You realize, in some ways, they're converging.

http://en.wikipedia.org/wiki/Larrabee_(GPU)

GPUs excel at tasks requiring massive parallelism.
If all the compute power could be harnessed with 100%
efficiency, the compute power approaches a teraflop.
(HD 4800 series).

Running a copy of Microsoft Office, has relatively
little parallelism. Thus the CPU is the right critter
to use for Microsoft Office.

While other things, like running Photoshop filters,
could be many times faster if they were run on the GPU.
And Adobe has just announced it has ported some filter
code in Photoshop, to run on the GPU.

Some GPGPU code, has accelerated the functions coded by
25x. So a GPU can definitely speed up some things. But
when there is only one thread of execution, the CPU
is going to leave that GPU in the dust. (The CPU has
a 3GHz clock, while the GPU clock is a lot slower.)

http://en.wikipedia.org/wiki/Gpgpu

So it is a very uneven match. In some ways, just as
complicated and confusing, as deciding whether to
buy a quad core CPU or not. Many people will own quad
core CPUs, and most of the time, three of the cores
aren't doing anything.

Each has its own niche, and things it is good at.
So there is room for both functions.

Will Intel and Nvidia attempt to raid one another's
territory ? You can count on it :)

(I mention Nvidia, simply because they're so interested
in antagonizing Intel. It's like they want a black eye.
And Intel is the company to give them one. Intel needs
competition, to keeps it's employees from falling
asleep. A little boxing with Nvidia, helps keep them
in shape.)

Paul
 
D

Dave

RC said:
This may seem like a stupid question, but what is the difference
between a CPU and a GPU.
I know one does graphics and makes it possible to play games or use
software they couldn't without one.
But, really, what it is processing is numbers, so why is one better at
certain tasks?
In the past, a CPU did both functions, but now it can't keep up.
Even a duel core computer can benefit from a GPU. So it would seem a
GPU can do more then a CPU. (Maybe maybe not.)
But if it can, why not use them as a CPU.
Or instead of a quad core system, why not a system with 2 CPUs and 2
GPUs on the MB. I mean real GPUs no the BS they try to pass off as
GPUS - GPUs that may let you play such cutting edge games as Commander
Keen, or the SOD series.

Yes, I have little understanding in this area and would be most
appreciative if someone could help me sort it all out.

RC

That isn't a stupid question at all. Very soon, the CPU, as we currently
know it, will be replaced by the GPU. The GPU is getting so powerful now
that it would be trivial to add CPU functions to a GPU. AMD already has
multi-core CPUs and they own ATI. How difficult do you think it would be
for AMD to put out a multi-core chip with both functions?

And that is the way that the industry is headed. Many though that AMD
buying ATI was a stupid decision. But seeing as the CPU is almost obsolete,
it was the ONLY decision AMD could have made, to insure long-term survival.

Looking forward even further...eventually all functions will be performed by
one card. The GPU integrated on the card will have a "core" to handle CPU
functions. Think of it as a motherboard, video card and CPU all in one.
It's coming. I'll be shocked if we don't get there within 10 years.

So your question is not stupid at all. CPUs and GPUs do perform slightly
different functions, but the power of a GPU is such that, if it is reworked
to act as a CPU, the CPU workload won't even slow it down
ignificantly. -Dave
 
S

sbb78247

Paul said:
You realize, in some ways, they're converging.

http://en.wikipedia.org/wiki/Larrabee_(GPU)

GPUs excel at tasks requiring massive parallelism.
If all the compute power could be harnessed with 100%
efficiency, the compute power approaches a teraflop.
(HD 4800 series).

Running a copy of Microsoft Office, has relatively
little parallelism. Thus the CPU is the right critter
to use for Microsoft Office.

While other things, like running Photoshop filters,
could be many times faster if they were run on the GPU.
And Adobe has just announced it has ported some filter
code in Photoshop, to run on the GPU.

Some GPGPU code, has accelerated the functions coded by
25x. So a GPU can definitely speed up some things. But
when there is only one thread of execution, the CPU
is going to leave that GPU in the dust. (The CPU has
a 3GHz clock, while the GPU clock is a lot slower.)

http://en.wikipedia.org/wiki/Gpgpu

So it is a very uneven match. In some ways, just as
complicated and confusing, as deciding whether to
buy a quad core CPU or not. Many people will own quad
core CPUs, and most of the time, three of the cores
aren't doing anything.

Each has its own niche, and things it is good at.
So there is room for both functions.

Will Intel and Nvidia attempt to raid one another's
territory ? You can count on it :)

have you looked into nVidia's CUDA? sounds like they are loading a lot of
cpu function to the gpu? admittedly I have not looked at in depth yet, but
it does sound interesting.

(I mention Nvidia, simply because they're so interested
in antagonizing Intel. It's like they want a black eye.
And Intel is the company to give them one. Intel needs
competition, to keeps it's employees from falling
asleep. A little boxing with Nvidia, helps keep them
in shape.)

Paul


--
sbb78247

resident redneck alt.os.windows-xp
alt.os.windows-vista

somebody pass the mashed potatoes and gravy
 

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