Dead AT power supply

I have a slot1 PC that won't power on. My roommate reports that something
smelled burnt when it suddenly powered off. When I checked it out the system
would only power on for a short spurt then go dead after a second, so I'm
suspecting the PSU is shot. Unfortunately, the power connectors on the PSU
consist of 2 6pin connectors and a 3pin standby power connector. I'm assuming
that the unit is an AT model, but I don't know where to find one that has a
standby power connector. Any suggestions other than "buy a new PC" would be
appreciated.

Ed Coolidge wrote:
I have a slot1 PC that won't power on. My roommate reports that
something smelled burnt when it suddenly powered off. When I checked it
out the system would only power on for a short spurt then go dead after
a second, so I'm suspecting the PSU is shot. Unfortunately, the power
connectors on the PSU consist of 2 6pin connectors and a 3pin standby
power connector. I'm assuming that the unit is an AT model, but I don't
know where to find one that has a standby power connector. Any
suggestions other than "buy a new PC" would be appreciated.

It's an AT PSU, from a particular manufacturer, but you gave no clue as to
who made the computer.

It could be the PSU or anything in the computer that's failed (CPU or
motherboard being common failure points in addition to the PSU) and
overloading it.

In article et,
Ed Coolidge wrote:
I have a slot1 PC that won't power on. My roommate reports that something
smelled burnt when it suddenly powered off. When I checked it out the system
would only power on for a short spurt then go dead after a second, so I'm
suspecting the PSU is shot. Unfortunately, the power connectors on the PSU
consist of 2 6pin connectors and a 3pin standby power connector. I'm assuming
that the unit is an AT model, but I don't know where to find one that has a
standby power connector. Any suggestions other than "buy a new PC" would be
appreciated.


Dumpster, flea market, yard sale.

--
a d y k e s @ p a n i x . c o m

Don't blame me. I voted for Gore.

The PC is an Acer Power 8000, or at least that's the best I can determine as
Acer has no record of the serial number. The only change that's been made was a
CPU upgrade that's been working fine for a month. I've unplugged all of the
drives and removed all of the cards except memory and video so I know it's not
overloaded. I tested it with the old CPU, but the results are the same. The PC
only has one 128MB RAM card and I don't have any spare RAM to test with it. I
tested the RAM a few weeks ago and it checked out OK. The power LED on the case
does light orange if that helps. I suspected that it might be the mainboard
too, but without swapping out the PSU I have no way to tell.

David Maynard wrote:

It's an AT PSU, from a particular manufacturer, but you gave no clue as
to who made the computer.

It could be the PSU or anything in the computer that's failed (CPU or
motherboard being common failure points in addition to the PSU) and
overloading it.

Al Dykes wrote:

Dumpster, flea market, yard sale.

Yes, but I don't believe that standby power connectors are common for AT units.
I would swap the PSU and the mainboard, but I don't know where to find a slot1
board on short notice as my roommate wants his PC back.

Just a thought, is there any way to start the PSU without the mainboard? All it
should need is the right signal on the standby connector, but I'm not sure what
that would be.


David Maynard wrote:


It's an AT PSU, from a particular manufacturer, but you gave no clue as
to who made the computer.

It could be the PSU or anything in the computer that's failed (CPU or
motherboard being common failure points in addition to the PSU) and
overloading it.

Ed Coolidge wrote:

Just a thought, is there any way to start the PSU without the
mainboard? All it should need is the right signal on the standby
connector, but I'm not sure what that would be.

There probably is but I can't find a pin out for the 3 pin connector, off hand.

You could try disconnecting the two 6 pin jobs and try powering it up with
the 3 pin still in the motherboard and hope the on/off switch works.


David Maynard wrote:


It's an AT PSU, from a particular manufacturer, but you gave no clue
as to who made the computer.

It could be the PSU or anything in the computer that's failed (CPU or
motherboard being common failure points in addition to the PSU) and
overloading it.

Ed Coolidge wrote:

The PC is an Acer Power 8000, or at least that's the best I can
determine as Acer has no record of the serial number. The only change
that's been made was a CPU upgrade that's been working fine for a
month. I've unplugged all of the drives and removed all of the cards
except memory and video so I know it's not overloaded. I tested it with
the old CPU, but the results are the same. The PC only has one 128MB
RAM card and I don't have any spare RAM to test with it. I tested the
RAM a few weeks ago and it checked out OK. The power LED on the case
does light orange if that helps. I suspected that it might be the
mainboard too, but without swapping out the PSU I have no way to tell.

Well, I found the user manual for it and it shows the connectors on the
motherboard but, interestingly enough, it doesn't say to plug the 3 pinner
in when installing a PSU.

You may have to get one from an Acer distributor.


David Maynard wrote:

It's an AT PSU, from a particular manufacturer, but you gave no clue as

to who made the computer.

It could be the PSU or anything in the computer that's failed (CPU or
motherboard being common failure points in addition to the PSU) and
overloading it.

I can't find any info on the pin out either. Just for kicks I checked it
without the 2 6pin connectors and the PSU fan starts up as soon as I connected
the power cord. The switch didn't make any difference. So if it's the
mainboard that's failed I would have to replace the PSU anyway.

David Maynard wrote:


There probably is but I can't find a pin out for the 3 pin connector,
off hand.

You could try disconnecting the two 6 pin jobs and try powering it up
with the 3 pin still in the motherboard and hope the on/off switch works.

Again, just for kicks, I figured that if the PSU is indeed on when connected
with only the standby connector it should be able to power a drive, so I tried
connecting a CD drive. At first it just wouldn't budge, but then I thought that
having ground to the host controller might be the problem, so I tried it again
without the data cable. the drive spun up just fine and the tray worked too. So
what do you think, dead mainboard?

Ed Coolidge wrote:

I can't find any info on the pin out either. Just for kicks I checked
it without the 2 6pin connectors and the PSU fan starts up as soon as I
connected the power cord. The switch didn't make any difference. So if
it's the mainboard that's failed I would have to replace the PSU anyway.

David Maynard wrote:


There probably is but I can't find a pin out for the 3 pin connector,
off hand.

You could try disconnecting the two 6 pin jobs and try powering it up
with the 3 pin still in the motherboard and hope the on/off switch works.