How to test a power supply?

[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.

 

[almaz]

http://cgi.ebay.com/New-PC-ATX-2-03...840690486QQcategoryZ44949QQrdZ1QQcmdZViewItem

 

[old jon]

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.

Green wire to any black.
bw..OJ

 

[Doug Kanter]

Green wire to any black.
bw..OJ

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.

 

[kony]

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.

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.