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Old February 10th 05, 12:47 AM
Richard Hopkins
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"baj2k" wrote in message...
First of all thanks for the thorough and very informative reply.


No worries. :-)

I've done some case baffling, dropped average case, CPU
and PWM temps under Prime95 maximum torture settings
by ~3c. While significant I'm assunig that's not enough.


Not really. Other folks here may have different opinions of course but if
that were my system I'd like to see the PWM temp significantly lower, and
the CPU cooling improved enough to eliminate the throttling.

but what is the maximum CPU and PWM temp's you'd be comfortable
running.


As I say, opinions may vary but I wouldn't be truly comfortable with the
whole thing until the PWM temp was down below 55C or so under load. The CPU
temperature is a slightly different case. Prescotts run hot, and there's
very little you can do about that. However, you need to cool it sufficiently
well enough that it doesn't throttle. If it does, there's very little point
running it at the sort of speeds you are, as, if all it does is throttle
whenever you use it, you're not actually getting the performance you should
be, if you see what I mean.

This thing ran in the high 60's C on Prime95 at stock 200MHz
/ 3.0GHz CPU speed. I'd say it gained ~ 8-10C at 267MHz.


Yeah, this is the problem with these bloody things unfortunately. Fricking
silly power consumption and heat dissipation before you even start
overclocking.

Here's the ThrottleWatch data @ 4.005GHz The first throttled data
point was at CPU temp of 68c. No throlling seemed to occur until
that temp.


Indeed. What you then need to aim for is a situation where you can keep the
CPU under this temperature, even under sustained and full utilisation.

Max temp was 72.5C +/-5C on CPU and 71.5C +/-5C on
PWM; temp fluctuates up and down quite a bit on the ABIT EQ
monitoring app, but never exceeded ~ 77C.


The throttling prevents the CPU from lunching itself by inserting increasing
amounts of halt cycles once the temperature starts to reach danger level.
This is a handy safety mechanism, but it also means that any gains you make
from overclocking are going to be offset - and possibly even lost
completely - if the throttling is severe.

Average load 52%
Average throttling 34%


That's a significant statistic. I haven't done any in-depth testing with
ThrottleWatch, primarily because my setup doesn't run hot enough to
throttle, and thus don't know whether its readings pan out in reality.

If they do, in effect it means that your 4.005GHz CPU turns into something
like a 2.65GHz CPU whenever you try and do anything significant with it. If
the ThrottleWatch results are correct, it also, significantly, means that
you're getting less performance at 4GHz than you would at the CPU's default
speeds - provided of course that CPU then ran cool enough to keep it under
the throttle threshold.

Prime95 Benchmark Results:


As a matter of interest, have you tried running Prime at default CPU speed?
It'd be interesting to see how the results compare, and whether the
throttling is indeed impacting performance to the extent ThrottleWatch is
suggesting.
--


Richard Hopkins
Cardiff, Wales, United Kingdom
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