trader_4 wrote:
On Tuesday, April 1, 2014 1:00:21 PM UTC-4, Tony Hwang wrote:
wrote:
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
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.
Some bad caps will also make the computer not boot. Or make the
computer crash when it gets warm.
Hi,
It all depends which part of the logic the cap is located. Until
you see some thing caused by any component going bad you wouldn't
believe things happening in the field(real world). Bad cap even scres up
critical rise and fall time of a clock pulse. My job as a Sr. systems
support specialist was looking at this sort of things with multi channel
logic analyzer set up to catch things when it happens. Some things
glitch once in a blue moon but we know it is happening and we have to
catch it to generate engineering mod. with design engineers.
I agree with the above analysis. But we're talking about a failing leaky
electrolytic cap causing the system speed to slow down. AFAIK, the
uses for electrolytic caps in a PC are either in the power supply or on
the MB, I/O boards, etc where power enters the board to serve as a
source to smooth voltage variations, ie supply current to meet transient
switching needs. At least for anything to do with logic. They would
also be used on say an audio or video card for the analog section.
But in the case of the digital logic portion, I can see how a bad cap
could easily make the system lock up, give a blue screen of death, etc.
But like others here, I'm having a hard time understanding a mechanism
whereby it just slows it down. I suppose maybe a failing cap on
some I/O board or something could cause that to behave erratically,
causing the same interrupt signal being tripped constantly, which the
CPU then has to respond to. That might explain it I guess.
Hi,
Slowing things down can mean increased error rate which require retries.
If cap is leaky(not total failure yet), it can sag voltage rail
potential. You're talking in terms of PC in general? Like BSOD? There
was such a logic board with CML logic which used to draw couple hundred
Watts of power, in this case little leaky cap is not detrimental for
system failure but it can cause all kinda funnies. In a situation like
this years of actual field experience combined with superior basic
knowledge is the only way to tacckle it. Engineers
with green horns don't even have a faintest clue encountering this kinda
issues when customer(big corporations, government, military, etc.) is
breathing down on his back asking when system will be up.
Literally I saw a young kid breaking down in tears in total loss.
Remembering I was once like that I always tried to be nice to them
giving every thing to their credit. But there were types who tried to
live their lives only with BIG mouth. I hated those kind. Usually big
liars to cover their a**. This type is the worst one to bail out.
Because of those stupid lies. I am glad I am retired now. I have a 100%
track record. I never failed to solve a problem in the field(all over
the world) I encountered for almost 40 years.