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Scott Lurndal

writes:
On Mon, 31 Mar 2014 19:57:54 GMT, (Scott Lurndal)
wrote:

writes:
On Mon, 31 Mar 2014 09:45:51 -0400, "Mayayana"

Both the Win7 dual CPU box and my new XP box, with
"mediocre" AMD A6 2-core, respond instantly. I keep them
clean. If you find you need a high-power machine for
speed to do things less intensive than video editing then
you probably have a lot of crap weighing down the system...
And you've probably been reading too many mainstream
media articles written by tech journalists who depend on
hardware and software companies for ad dollars. The world
of tech survives on a dizzying pace of forced obsolescence,
so if you go by what the media tells you you'll end up
replacing gadgets as fast as you buy them.

Computers of that age have another common failure mode that slows them
to a crawl - leaky caps.

Can you clarify how a leaky cap will "slow them to a crawl"?

If the PLL controlling the clock signal doesn't lock at the
target frequency, the processor will never leave reset. I suppose
that qualifies as "slow", for some value of "slow".
I'm not a computer engineer, but I have experienced computers slowing

In 40 years of computer engineering, I've not experienced this. I've
seen caps blow up (and blow right out the side of the mainframe). I've
seen bad caps let the magic smoke out. I've seen dead caps prevent a
system from booting.

I've never seen, nor heard of a cap causing a PC to slow down. Not
that I'm discounting your experience, I'm just not sure that you've
correctly attributed the problem to the capacitors.

to a crawl with bad caps, that came right back to life when I replaced
the caps. It's not just the processor clock - it's the IO from the
hard drive, the refresh rate on the RAM, and the output to the video
that can all slow down. The processor misses clock cycles if the
voltage goes off spec too, from what I've been told.

You've been told incorrectly. Once you've exceeded the tested
margins for the voltage or frequency, system operation is
unpredictable. That said, most modern processors use DVFS (Dynamic
Voltage and Frequency scaling) to dyamically reduce power
consumption by varying both within margins.

Some bad caps will also make the computer not boot. Or make the
computer crash when it gets warm.

The former, true, the latter, not so much (it's other components
that can't stand the heat).