Chipsets and memory speed...
hahn at coffee.psychology.mcmaster.ca
Tue Dec 12 17:42:35 PST 2000
> Anyone know the difference in bandwidth/stream performance between a PC with
> a Duron vs an Athlon cpu? Is there much/any difference?
none: duron and thunderbird differ only in size of onchip cache
(192K vs 384K - those are actual capacities; coppermine's is 256K).
> I looked at the stream benchmark pages, but didn't find any benchmarks using
> the Duron.
Function Rate (MB/s) RMS time Min time Max time
Assignment: 525.1589 0.0305 0.0305 0.0306
Scaling : 505.7214 0.0317 0.0316 0.0317
Summing : 553.1737 0.0434 0.0434 0.0435
SAXPYing : 523.9031 0.0458 0.0458 0.0459
that's for a duron/600, 128M PC133 sdram (cas2, I think - bios doesn't say).
it's interesting to consider the "efficiency" of various cpu/northbridge/dram
combinations. the above machine delivers 500-550 MB/s out of a theoretical
(never-possible) 1066 MB/s: 47% efficiency. good old PII/bx/PC100 boxes
would deliver 3-400 MB/s out of 800 MB/s: around the same efficiency.
i840 machines seem to max out at around 550 MB/s out of 3200, for a record
of around 17% efficiency! otoh, rumor has it that i850's deliver more like
1400/3200, back into the 40-50% range, and well into Alpha territory...
of course, stream doesn't credit the machine for write-allocate traffic,
which would "improve" the numbers by 3/2 or 4/3...
regards, mark hahn.
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