What makes Centrino so fast?

Daniel O'Connor doconnor at gsoft.com.au
Sat Mar 13 22:06:38 PST 2004


On Sun, 14 Mar 2004 15:41, David Schultz wrote:
> > but in short.. better branch prediction, and micro-architecture
> > improvments in general, and a slightly longer pipeline (for higher clocks
> > vs a PIII)
>
> You're right that the longer pipeline allows the processor to be
> clocked higher, but for a *given* speed (e.g. 1700 MHz), a longer
> pipeline is actyually a disadvantage; longer pipelines cause more
> stalls and higher branch misprediction costs.  The better branch
> predition merely attempts to hide the penalty of the longer
> pipeline.  I don't know why the Centrino performs better than the
> Athlon in this case, though.  If you really care, you'll probably
> have to factor the benchmark into specific, simple tests that
> demonstrate the performance difference, play with compiler
> optimizations, etc.

I said the longer pipeline was for higher clocks, the improved branch 
prediction could have a benefit over and above the penalty imposed by a 
longer pipeline, but as always I would imagine it would depend on the type of 
code being run through it :)

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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