[Beowulf] crunch per kilowatt: GPU vs. CPU

[Joe Landman]

Nifty Tom Mitchell wrote:
> On Mon, May 18, 2009 at 01:35:43PM -0400, Joe Landman wrote:
>> David Mathog wrote:
>>> Although the folks now using CUDA are likely most interested in crunch
>>> per unit time (time efficiency), perhaps some of you have measurements
>>> and can comment on the energy efficiency of GPU vs. CPU computing?  That
>>> is, which uses the fewest kilowatts per unit of computation.  My guess
>> Using theoretical rather than "actual" performance, unless you get the  
>> same code doing the same computation on both units:
> 
> Another issue is the upgrade cost and upgrade potential.  Looking across
> my room I see an older AMD-64bit single core Athlon box.   It would be
> less expensive and much less of a task to swap out and upgrade the GFX
> card than it would be to update the processor.   In some cases multiple
> GFX cards are also possible.
> 
> Also it makes little sense for me to upgrade the GFX card based on
> graphics display needs only.   If I toss CUDA in the mix a high end
> GFX card upgrade does get interesting.

What makes this very interesting is that you can get reasonable CUDA 
performance for a number of apps for ~$500.  Add in the powersupply you 
will likely need ($300) to support more than one card ...

... the cost benefit analysis just keeps getting better ... *if* your 
code can use it.  There is no guarantee on this, but it is worth 
considering.



-- 
Joseph Landman, Ph.D
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