none (none.delete@this.none.com) on February 4, 2013 4:28 pm wrote:
> Michael S (already5chosen.delete@this.yahoo.com) on February 4, 2013 1:39 pm wrote:
> > Patrick Chase (patrickjchase.delete@this.gmail.com) on February 4, 2013 11:55 am wrote:
> > > Patrick Chase (patrickjchase.delete@this.gmail.com) on February 4, 2013 11:47 am wrote:

> > > There is also an issue of external DRAM bandwidth. The PIII-500's chipsets used a single 64-bit SDR SDRAM
> > > channel if I recall correctly. Peak STREAM bandwidth was on the order of a couple hundred MiB/sec.
> > >
> >
> > Slightly more:
> > Intel_440BX_600, ncpus=1 - 342.2/340.2/412.0/409.2
> > http://www.cs.virginia.edu/stream/stream_mail/1999/0035.html
> >
> > > The Origin used 128-bit DDR per node (it's a NUMA), so it would have had ~4X the bandwidth
> > > to memory on even a single node. Peak STREAM bandwidth was close to 1 GiB/sec.
> >
> > Unfortunately, I can't find single-CPU STREAM result for Origin 3200.
> > The previous Origin generation is not very good in single or dual CPU mode:
> > SGI_Origin2000-300, ncpus=1 - 336.0/334.0/387.0/388.0
> > SGI_Origin2000-300, ncpus=2 - 383.0/373.0/414.0/422.0
> > SGI_Origin2000-300, ncpus=4 - 759.0/754.0/852.0/854.0
> >
> > The smallest Origin3k on official site is a quad:
> > SGI_Origin3800-400, ncpus=4 - 1400.6/1403.1/1551.5/1574.3
> >
> > 4-cpu score is twice higher than Origin2000-300, but I am not sure
> > that we can conclude that the same ratio applies to a single CPU.
>
> Page 9 of http://www.sgi.co.jp/origin/ODP/documents/products/performance/o3k600/3000_600perfrep3.pdf
>
> 1 core is 733 / 673 / 766 / 773.
>

Thank you.

So R14K in Origin3k has approximately 2x advantage in Stream bandwidth over identically clocked Pentium-III.
On the other hand R10K in PowerChallenge10k has about the same Stream bandwidth as PPro.
That's not a bad explanation for big difference in SpecFp ratios between two pairs.