To my knowledge, the effect on performance of burn-in has not really
been widely discussed or explored; at least not on any of the main
overclocking forums which I am aware of.
Which is partly why I raised the question.
Some things are known to happen; and I have observed them myself. First,
the amount of voltage required to work at a given speed decreases.
Secondly, the odds of the chip working at a higher speed increases.
This much is common knowledge. No one has satisfactorily explained
these results, though many theories abound.
There are also rumors that the higher-quality chip cores, which get put
into the C333A/366/400 and Pentium II's are measureably faster. These
rumors have not been confirmed to my knowledge.
What I was saying was that an improvement in speed was not unexpected;
I.e. it is consistant with the expected improvement in the chip due
to burn-in. These are also my own expectations.
It would be difficult to classify unexplored territory as "common knowledge".
Perhaps it's common knowledge to some; it's just not mentioned in the
more popular websites or forums.
-dwight-
> From [EMAIL PROTECTED] Wed Jan 13 18:17:14 1999
>
>
> This brings up an interesting question (Well at least to me it is). I
> notice that you refer to the iteration time "going down" as an expected
> event. Are you saying that a new CPU is expect to get faster (If ever so
> slightly) after an initial "Burn in" time??? Perhaps that is a bit of
> common knowledge I have never heard of. Can someone explain this in
> greater detail?
>
> Thank You,
>
> Chuck
>
> On Wed, 13 Jan 1999, Leu Enterprises Unlimited wrote:
>
> >
> > Greetings!
> >
> > Aside from it's normal uses, I've been looking at using mprime as
> > a QA and benchmarking tool.
> >
> > This is particularly important for overclocked Beowulf clusters,
> > where reliability is a must. And given that the price of these
> > is now so cheap (with a Gigaflop being achieved for under $10,000),
> > adaquate Q.A. procedures are a must. Re: my observations on
> > www.supercomputer.org.
> >
> > I've recently noticed something interesting. Namely, with the so-called
> > effects of "burning-in" a CPU via mprime's torture test, and the
> > resulting effects on the CPU speed (as determined by the mprime
> > time test).
> >
> > On one CPU, after two days worth of burn-in, the time required to
> > complete 100 iterations on the stock number went down, as I would expect.
> >
> > On a second CPU, the time actually *increased*. From 1 day, 18 hours,
> > and 55 minutes, to 1d 19h 13m!
> >
> > So this leads me to wonder if what I'm seeing is real, or whether
> > mprime is really sensitive enough to be used here. The O.S. being
> > used is Linux.
> >
> > If mprime is indeed seeing some real effects here, I think people
> > need to be aware of it. Or even if it's not suitable for this, people
> > should also know.
> >
> > If anyone knowledgeable would care to comment about mprime's suitability
> > for Q.A. and/or performance measurements, I would appreciate it.
> >
> > Thanks!
> >
> > -dwight-
> >
