Yes, MHz does make a difference, but people need to please stop touting SPEC results without taking into account other factors when comparing CPU performance...
SPEC benchmarks are designed with minuscule datasets to reduce RAM and Cache bottlenecks... some interesting articles found at the STREAM homepage discuss how some CPU manufacturers boosted L2 cache on their chips, while ignoring RAM bandwidth considerations, simply to get higher SPEC results... Memory bandwidth results (MByte/s) for recent HP, RS/6000, and esp. Alphas single-CPU workstations show they can play around with much more data located in RAM alot quicker than a 733 PIII, even at low clock speeds (400MHz for POWER3 and PA-RISC 8500... the Alphas were 21264s clocked at equal to or slightly less than 733MHz, with results being about double those of the PIII)... note that the PIII wasn't a xeon... shouldn't make a big diff though, because the architecture is similar (nearly identical) for PIII and PIII-xeon... look at the results yourselves, it's innarestin...
that being said, all Sun Ultra workstations performed a little worse than 'equivalent' HP, IBM, and DEC(Compaq) workstations regarding RAM bandwidth... Ultra60-360s perform so poorly that the PIII 733 gets twice as many MFLOPS on a particular test (but the lead is much less on two others... a 450MHz-Ultra might tie or surpass them)...
And ALL that to say that SPEC is only useful if you're comparing systems which will be doing computations on teeny tiny datasets. At least that's the case for SPECcpu95, I don't know about SPECcpu2000. Furthermore, the SPECfp benchmarks focus mainly on double-precision floats, to the expense of single-precision floats... this might indicate why results for SGI machines make them look pokey, considering some of their CPUs (r5000) are optimized for single-precision MADD instructions, because of their ubiquity in doing 3D work...
nuh unh... their IRIS 1000/2000/3000 series' use 680x0. I believe it was only around 1986 that the move towards MIPS began. The 3000 series finally ended production in 1989.
"a good background for which would be available from Neal Stephenson's book 'Zodiac'." It's just cruel using freakish syntax like this when I'm wondering if my brain's been PCBed all to hell...
lotsa juicy stuffs... has some tech specs too... but remember that spec isn't the be-all end-all measure of a machine, just a neat l'il tool for cpu power, nothing else (sometimes not EVEN for cpu power... ie. it can't measure everything)...
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Yes, MHz does make a difference, but people need to please stop touting SPEC results without taking into account other factors when comparing CPU performance...
SPEC benchmarks are designed with minuscule datasets to reduce RAM and Cache bottlenecks... some interesting articles found at the STREAM homepage discuss how some CPU manufacturers boosted L2 cache on their chips, while ignoring RAM bandwidth considerations, simply to get higher SPEC results...
Memory bandwidth results (MByte/s) for recent HP, RS/6000, and esp. Alphas single-CPU workstations show they can play around with much more data located in RAM alot quicker than a 733 PIII, even at low clock speeds (400MHz for POWER3 and PA-RISC 8500... the Alphas were 21264s clocked at equal to or slightly less than 733MHz, with results being about double those of the PIII)... note that the PIII wasn't a xeon... shouldn't make a big diff though, because the architecture is similar (nearly identical) for PIII and PIII-xeon... look at the results yourselves, it's innarestin...
that being said, all Sun Ultra workstations performed a little worse than 'equivalent' HP, IBM, and DEC(Compaq) workstations regarding RAM bandwidth... Ultra60-360s perform so poorly that the PIII 733 gets twice as many MFLOPS on a particular test (but the lead is much less on two others... a 450MHz-Ultra might tie or surpass them)...
And ALL that to say that SPEC is only useful if you're comparing systems which will be doing computations on teeny tiny datasets. At least that's the case for SPECcpu95, I don't know about SPECcpu2000. Furthermore, the SPECfp benchmarks focus mainly on double-precision floats, to the expense of single-precision floats... this might indicate why results for SGI machines make them look pokey, considering some of their CPUs (r5000) are optimized for single-precision MADD instructions, because of their ubiquity in doing 3D work...
Here are some sites that contain benchmark results and/or link to sites with benchmark results:
SPEC website
the CPU Info Center
FutureTech SGI info
It's Ace's Hardware, and here's the article.
nuh unh... their IRIS 1000/2000/3000 series' use 680x0. I believe it was only around 1986 that the move towards MIPS began. The 3000 series finally ended production in 1989.
"a good background for which would be available from Neal Stephenson's book 'Zodiac'."
It's just cruel using freakish syntax like this when I'm wondering if my brain's been PCBed all to hell...
http://bwrc.eecs.berkele y.edu/CIC/summary/local/summary.pdf
lotsa juicy stuffs... has some tech specs too...
but remember that spec isn't the be-all end-all measure of a machine, just a neat l'il tool for cpu power, nothing else (sometimes not EVEN for cpu power... ie. it can't measure everything)...
All good things,