How to test a power supply?

  • Thread starter Thread starter Doug Kanter
  • Start date Start date
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Doug Kanter

Thanks to everyone who contributed answers to various brands of power
supplies last week. Now, I need to confirm the problem really is the power
supply. I have a computer that simply doesn't power up. I've tested the
front panel switch, and the cord's fine, too. I've unplugged the power
connector from the mother board. Which wires do I have to short in order to
simulate the power switch being pressed?

The power supply is a Power Man IPS-1805V.
 
Doug Kanter said:
Thanks to everyone who contributed answers to various brands of power
supplies last week. Now, I need to confirm the problem really is the power
supply. I have a computer that simply doesn't power up. I've tested the
front panel switch, and the cord's fine, too. I've unplugged the power
connector from the mother board. Which wires do I have to short in order
to simulate the power switch being pressed?

The power supply is a Power Man IPS-1805V.
Click to expand...
Green wire to any black.
bw..OJ
 
old jon said:
Green wire to any black.
bw..OJ
Click to expand...

OK. The power supply is dead. Good. It's too small anyway. Who ever heard of
a 180 watt power supply? (This machine was built for my company by some
local outfit. You take out one screw and the entire cabinet falls apart).
:-) It's about to be pimped.
 
OK. The power supply is dead. Good. It's too small anyway. Who ever heard of
a 180 watt power supply? (This machine was built for my company by some
local outfit. You take out one screw and the entire cabinet falls apart).
:-) It's about to be pimped.
Click to expand...


It's not that simple.
Pin 14, PS-On shorted to a ground (like a black wire) is the
mechanism to turn one on BUT some PSU do not have internal
rail loading so they require a load to turn on... might
barely stutter a fan if one were connected but need at least
a drive connected, typically the manufacturers spec 2A on 5V
rail as the minimal load.
http://69.36.189.159/usr_1034/atx_on.gif

There's nothing wrong with a 180W supply if that's all the
system needs, and if it's a decent quality unit. In fact
the typical mATX supply is only good for about 200W so if
you found one rated for more, it's typically a sign the
manufacturer is dishonest, not that the PSU is worth higher
rating. In other systems, like older Compaqs, the PSU may
not be rated very high- sometimes even as low as 70-90W, but
they were very high quality for their wattage and might
outperform some of today's so-called 400W generics (like
Raidmax or Deer).

It might just be junk though, which would make the eventual
failure expected.
 
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