Look, no one is arguing against using a multi-meter or any
other tools to obtain numerical data. No one is saying that
such information is not needed, in certain circumstances.
But, in this case (and most cases), it would only provide data
as to whether the PSU was providing the voltages it needs to.
But even if you could establish a deeper understanding of why
the PSU wasn't functioning properly, the only thing that most
can do about it is replace the PSU.
Same point even made in CSI. Conclusions made by speculation are
not facts. We call it shotgunning.
Assume a second power supply boots the system. Well, first power
supply was perfectly good. But changing the power supply temporarily
fixed a loose connection. Failure returns later as observed in some
other posts asking these same questions. Fixing something without
*knowing* it was defective? Just another way to waste time and
money. Especially when identifying the defect takes so little time.
Is it a power supply or some other component of the power supply
'system'. Another part of shotgunning. We pretend those other
'system' components are not defective? Well the same numbers that
could identify a defective power supply with also define those other
components as either 'definitively good' or 'definitively bad'. The
only useful answer includes that word definitively - and takes less
time - and does not waste money replacing perfectly good components.
A defective power supply may still boot the computer. And a
perfectly good power supply sometimes may not boot in some computers.
Replacing parts in these situations means a problem remains.
Using the meter identified a defect in seconds. Swapping power
supplies takes so many more minutes - replacing a part that was not
defective. What happens if the failure is in another part of the
power supply 'system'? Do we blame memory, then CPU, then motherboard
as a flow chart said? How many parts (including power supply) do we
buy uselessly?
Power supply tester is a nearly useless tool. It can only identify
one extreme type failure. Meanwhile, the meter would identify or
eliminate that failure and a long list of other failures in seconds -
and definitively. Meter provides information so that the technically
better educated can reply with additional useful suggestions. No
meter numbers means better informed need not bother to reply. No
numbers means shotgunning. Anyone can do that without assistance
here. A defective power supply (it spins fans and illuminates lights
but will not boot) can still be declared good by that power supply
tester. That power supply tester is typical of conclusions made
without numbers. Incomplete. Not definitive.
First numbers from a meter identify the defect in seconds. Then the
new power supply is installed and also checked. If computer boots,
then is a power supply OK? Of course not. A defective (or
undersized) supply can still boot a computer. That new supply is not
known good until verified by the meter.
After a new power supply is installed, the meter checks that supply
while computer provides a maximum load (multitasking to all
peripherals simultaneously). Meter also calibrates the motherboard
voltage monitor (if it exists). Meter next checks the CMOS battery
(without removing it). If that 3 volt battery is about 2.8 volts,
then make plans to replace that battery in the next six months. Just
another failure that need not crash a computer.
Will the power supply tester do any of this? Will a power supply
tester test other parts of the power supply 'system'? No for both
questions. Why spend so much for a tester that does so little? It
will not even say a power supply is good - definitively. Many fear a
device that gives numbers. 'Safer' is a device that only has lights.
But the informed person buys a multimeter - a tool for fixing
virtually anything electrical - for maybe $7 more. The meter has
usefulness equivalent to a hammer. The power supply tester may even
be useless with a next generation power supply - and has no other
useful function - for so much money.
