On 6/2/26 15:47, Joe wrote:
On Tue, 2 Jun 2026 15:06:20 -0400
Dan Ritter <[email protected]> wrote:
David Christensen wrote:
On 6/2/26 07:02, Stefan Monnier wrote:
I've seen too many hard-to-diagnose problems that disappeared
after replacing a sketchy PSU. Random hangs and crashes, hard
drive errors, video noise, hang on reboot, etc. I no longer
try to go cheap when choosing a PSU for builds.
Yeah, I'm actually surprised the hardware hasn't caught on
accordingly: while it's now standard for chips to monitor their
temperature (and adjust their power consumption if it gets too
high), I still haven't seen anything comparable that would detect
and report when the input voltage goes out-of-range (and maybe
also take steps to reduce the instantaneous power consumption?).
https://en.wikipedia.org/wiki/Lm_sensors
lm_sensors (Linux-monitoring sensors) is a free open-source
software-tool for Linux that provides tools and drivers for
monitoring temperatures, voltage, humidity, and fans. It can also
detect chassis intrusions.
Almost all of those sensors are on the motherboard or on
attached cards; you'll frequently get to see voltages from the
CPU, but hardly ever does a power supply tell you about its
load.
They are also going to be polled, and will return the voltage they find
at polling time. What they won't tell you is what various ripple
voltages are, both the initial rectified mains at 100/120Hz and the
residual switching frequencies of the various step-down regulators.
Under some combination of conditions, including temperature, the
combinations of ripple may allow a regulator output to drop out of spec
for a microsecond, more than enough to corrupt a signal on e.g. a SATA
line. Further, this may only happen once a week or so.
Increasing ripple voltage is what happens when smoothing capacitor
electrolytes dry out, which they will eventually do with age.
Einstein allegedly said:
"Insanity is doing the same thing over and over again and expecting
different results"
He had obviously never encountered the Intermittent Fault.
I may be al ittle slow upstairs, but how does this differ from
persistence??????? Just asking! :-)
