Power supply fried, replaced it, computer won't start

"." wrote in message
...
In article ,
"Rod Speed" wrote:

Unplug everything except the motherboard
and see if the cpu fan comes on and stays on.

If it does, plug the hard drive in and see if it will boot
with just the motherboard and hard drive connected etc.

Thanks to you and all who responded.

My original post asserted that I wasn't an engineer. True. But I
solved the problem with your advice above, thinking systematically like
an engineer. I disconnected the power supply and connected everything
one by one, and the computer is now fully functional. From a little
research I did, I think my issue was that I'd connected the 3.5" floppy
power incorrectly or partially.


AHHH the Ole floppy power connector woes...damn stupid
connector.......................

AFA PSUs go have a 6 year old codegen (touted the worst) still going
strong and a Antec that died in 3 months.
IOW its a crap shoot...


I also appreciate everyone's point about not being cheap. In 15+ years
of heavy computer use, i've never had a PSU go bad on me. But given all
the heartache this burnout caused, I'll from now on spend the extra
money for an Antec or other name brand supply. If I'd lost something
really important and known that an extra $40-50 would have averted the
disaster, I'd have been kicking myself.

.. wrote:
Yesterday morning, ten hours after I'd last powered my PC down, I turned
it on and noticed immediately a burning "electrical fire" smell.

Turned the computer off (using Windows shutdown first from the login
screen), disconnected all peripherals and the power, opened the case.
Attached the power cord only, started it, everything worked (hard drives
were cycling, CPU fan going, motherboard lights on, etc.), but I noticed
the smell again. I did some sniffing and it was definitely coming from
the power supply. Then the computer just stopped.

I am not a "hardware guy" but I did some research on the web, consulted
with the friend who helped me build the computer, and it seemed pretty
open and shut. The 350 watt supply that came with the case ($35 for
case and supply) was to blame.

So went to CompUSA today and picked up
http://www.compusa.com/products/prod...ct_code=283768 -
seemed to be a worthy "bang for the buck" 400-watt supply.

http://www.hardwaresecrets.com/article/362/ is the instructions I
followed.

Before disconnecting the old PSU, I carefully labelled every connection,
showing what it was connected to, and the orientation on the drive or
board. (The PSU had a 20-pin connection to the motherboard, the ATX12V
comnnector, and my computer has two hard drives, a DVD drive, and a 3.5"
floppy.)

Plugged the computer in, turned on the PSU, and nothing. Ultimately, I
tried a known good power cord and the new cord that came with the PSU, a
known working outlet, several permutations, nothing. The voltage
selector is correct (115 volts) on the back of the PSU. When I apply
power, the CPU fan turns for about two seconds then stops (no harsh or
unusual noises - it was turning fine yesterday). The green light on the
motherboard stays lit. But no drive lights come on, and no sign of any
activity.

I don't have a multimeter. I'm not an electrician or electrical
engineer. I just want some suggestions on what might be wrong and how
to fix it. FWIW, the motherboard seems to show no abuse; the capacitors
all look shiny and intact.

My friend who built the PC for me is traveling, and I will ultimately
bring the computer to him and his extensive testbench if I can't figure
this out myself. But I'm really at my wit's end now and am hoping for a
few useful "try this" suggestions.
I have had a powers supply smoke because the cord went bad but all it
did was fry the power supply and after that was replace all worked well
but perhaps yours did damage to some of the other components, the mother
board or the other cards. Check all your connections from the cast to
the motherboard and from the drives to the mother board and from the
powr to the motherboard and to the drives. Make sure the RAM is seated
properly. There is no real guessing what happened It could have been a
power cord gone bad or a power surge.

.. wrote:
Yesterday morning, ten hours after I'd last powered my PC down, I turned
it on and noticed immediately a burning "electrical fire" smell.

Turned the computer off (using Windows shutdown first from the login
screen), disconnected all peripherals and the power, opened the case.
Attached the power cord only, started it, everything worked (hard drives
were cycling, CPU fan going, motherboard lights on, etc.), but I noticed
the smell again. I did some sniffing and it was definitely coming from
the power supply. Then the computer just stopped.

I am not a "hardware guy" but I did some research on the web, consulted
with the friend who helped me build the computer, and it seemed pretty
open and shut. The 350 watt supply that came with the case ($35 for
case and supply) was to blame.

So went to CompUSA today and picked up
http://www.compusa.com/products/prod...ct_code=283768 -
seemed to be a worthy "bang for the buck" 400-watt supply.

http://www.hardwaresecrets.com/article/362/ is the instructions I
followed.

Before disconnecting the old PSU, I carefully labelled every connection,
showing what it was connected to, and the orientation on the drive or
board. (The PSU had a 20-pin connection to the motherboard, the ATX12V
comnnector, and my computer has two hard drives, a DVD drive, and a 3.5"
floppy.)

Plugged the computer in, turned on the PSU, and nothing. Ultimately, I
tried a known good power cord and the new cord that came with the PSU, a
known working outlet, several permutations, nothing. The voltage
selector is correct (115 volts) on the back of the PSU. When I apply
power, the CPU fan turns for about two seconds then stops (no harsh or
unusual noises - it was turning fine yesterday). The green light on the
motherboard stays lit. But no drive lights come on, and no sign of any
activity.

I don't have a multimeter. I'm not an electrician or electrical
engineer. I just want some suggestions on what might be wrong and how
to fix it. FWIW, the motherboard seems to show no abuse; the capacitors
all look shiny and intact.

My friend who built the PC for me is traveling, and I will ultimately
bring the computer to him and his extensive testbench if I can't figure
this out myself. But I'm really at my wit's end now and am hoping for a
few useful "try this" suggestions.
I have had a powers supply smoke because the cord went bad but all it
did was fry the power supply and after that was replace all worked well
but perhaps yours did damage to some of the other components, the mother
board or the other cards. Check all your connections from the cast to
the motherboard and from the drives to the mother board and from the
powr to the motherboard and to the drives. Make sure the RAM is seated
properly. There is no real guessing what happened It could have been a
power cord gone bad or a power surge

Dave C. wrote:
"." wrote in message
...
Yesterday morning, ten hours after I'd last powered my PC down, I turned
it on and noticed immediately a burning "electrical fire" smell.

Turned the computer off (using Windows shutdown first from the login
screen), disconnected all peripherals and the power, opened the case.
Attached the power cord only, started it, everything worked (hard drives
were cycling, CPU fan going, motherboard lights on, etc.), but I noticed
the smell again. I did some sniffing and it was definitely coming from
the power supply. Then the computer just stopped.

I am not a "hardware guy" but I did some research on the web, consulted
with the friend who helped me build the computer, and it seemed pretty
open and shut. The 350 watt supply that came with the case ($35 for
case and supply) was to blame.

So went to CompUSA today and picked up
http://www.compusa.com/products/prod...ct_code=283768 -
seemed to be a worthy "bang for the buck" 400-watt supply.

http://www.hardwaresecrets.com/article/362/ is the instructions I
followed.

Before disconnecting the old PSU, I carefully labelled every connection,
showing what it was connected to, and the orientation on the drive or
board. (The PSU had a 20-pin connection to the motherboard, the ATX12V
comnnector, and my computer has two hard drives, a DVD drive, and a 3.5"
floppy.)

Plugged the computer in, turned on the PSU, and nothing. Ultimately, I
tried a known good power cord and the new cord that came with the PSU, a
known working outlet, several permutations, nothing. The voltage
selector is correct (115 volts) on the back of the PSU. When I apply
power, the CPU fan turns for about two seconds then stops (no harsh or
unusual noises - it was turning fine yesterday). The green light on the
motherboard stays lit. But no drive lights come on, and no sign of any
activity.

I don't have a multimeter. I'm not an electrician or electrical
engineer. I just want some suggestions on what might be wrong and how
to fix it. FWIW, the motherboard seems to show no abuse; the capacitors
all look shiny and intact.

My friend who built the PC for me is traveling, and I will ultimately
bring the computer to him and his extensive testbench if I can't figure
this out myself. But I'm really at my wit's end now and am hoping for a
few useful "try this" suggestions.

Poor quality power supplies have two very nasty habits:

1) They die early (that is GUARANTEED, btw), often shortly after leaving
the factory
2) With no built-in component protection, they often take other components
with them, when they die. In other words, cheap power supplies kill
motherboards, hard drives, CPUs, RAM, etc.

Your post is about TWO poor quality power supplies. I suspect that the
first one died ungracefully, taking the motherboard out with it. The second
one can't even power itself, apparently.

It's your money, but people don't seem to understand that often spending an
extra 40 bucks or so on a GOOD power supply can save a complete rebuild,
costing hundreds of bucks. -Dave

I would have to agree with Dave, After having a computer built for me
the power supply died on me about 1 year later. The burning smell and
everything that goes with it including entire computer shutting down .
After going to Store and buyng a new 400 Watt power supply, I asked how
a new power supply could fail in only 1 year. He replied it was
probably a cheap one if it was built in a retail store as some try to
cut corners and save money. I installed the new 60.00 power supply and
everthing worked fine...I was just lucky the MB or no other components
were fried.

Poor quality power supplies have two very nasty habits:

1) They die early (that is GUARANTEED, btw), often shortly after leaving
the factory
2) With no built-in component protection, they often take other components
with them, when they die. In other words, cheap power supplies kill
motherboards, hard drives, CPUs, RAM, etc.

Your post is about TWO poor quality power supplies. I suspect that the
first one died ungracefully, taking the motherboard out with it. The second
one can't even power itself, apparently.

It's your money, but people don't seem to understand that often spending an
extra 40 bucks or so on a GOOD power supply can save a complete rebuild,
costing hundreds of bucks. -Dave

Actually, I'm sure the power supply he bought from the store is
perfectly fine. Don't forget about "power good"! If the power supply
doesn't see this, it will not stay on. That is how all ATX power
supplies are designed, and it is indeed built-in component protection.
If anything is shorting out (as could very well be the case here, since
his first power supply fried something), it will shut down a working
power supply.

Also, people should pay attention and when smelling something burning, grab
the power cord and unplug it. In the OP, the poster said that he used the
Windows shutdown, etc. PULL THE PLUG!

Larry
Behold Beware believe

"Plato" |@|.| wrote in message
...
Lookout wrote:

If all you hook up to the power supply is the MOBO (no RAM or CPU) and
you can't even get to post (a beep, no beeps at all) then your problem
is probably (98%) a fried MOBO. Just hope it didn't go any further.

There are generally two things that cause a major smell when they burn
out:

1. Monitor
2. The Case Power Supply

The case power supply can, tho rare, also take out other parts in a
system when it goes bad or burns.


--
http://www.bootdisk.com/




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Posted via a free Usenet account from http://www.teranews.com

Larry Crites wrote:
Also, people should pay attention and when smelling something burning,
grab the power cord and unplug it. In the OP, the poster said that he
used the Windows shutdown, etc. PULL THE PLUG!

Yeah, that's kind of like sending a physical letter to the fire
department when you notice the garage is on fire.

--
Blinky RLU 297263
Killing all posts from Google Groups
The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html

"Blinky the Shark" wrote in message
...
Larry Crites wrote:
Also, people should pay attention and when smelling something burning,
grab the power cord and unplug it. In the OP, the poster said that he
used the Windows shutdown, etc. PULL THE PLUG!

Yeah, that's kind of like sending a physical letter to the fire
department when you notice the garage is on fire.

More like sending a letter to your doctor when you notice the garage on
fire........and then when you weren't quite sure there was enough
damage...... turn it on again......

David Matthew Wood wrote:


Poor quality power supplies have two very nasty habits:

1) They die early (that is GUARANTEED, btw), often shortly after leaving
the factory
2) With no built-in component protection, they often take other components
with them, when they die. In other words, cheap power supplies kill
motherboards, hard drives, CPUs, RAM, etc.

Your post is about TWO poor quality power supplies. I suspect that the
first one died ungracefully, taking the motherboard out with it. The second
one can't even power itself, apparently.

It's your money, but people don't seem to understand that often spending an
extra 40 bucks or so on a GOOD power supply can save a complete rebuild,
costing hundreds of bucks. -Dave

Actually, I'm sure the power supply he bought from the store is
perfectly fine. Don't forget about "power good"! If the power supply
doesn't see this, it will not stay on. That is how all ATX power
supplies are designed, and it is indeed built-in component protection.
If anything is shorting out (as could very well be the case here, since
his first power supply fried something), it will shut down a working
power supply.

Good link on the Power Good Signal
http://www.pcguide.com/ref/power/sup...werGood-c.html
and how "Some extremely el-cheapo power supplies may "fake" the Power
Good signal by just tying it to another +5 V line."

--
Board Dots
http://www.boredmuch.com/view.php?id=764

David Matthew Wood wrote

Poor quality power supplies have two very nasty habits:

1) They die early (that is GUARANTEED, btw),
often shortly after leaving the factory
2) With no built-in component protection, they often take other
components with them, when they die. In other words, cheap power
supplies kill motherboards, hard drives, CPUs, RAM, etc.

Your post is about TWO poor quality power supplies. I suspect that
the first one died ungracefully, taking the motherboard out with it.
The second one can't even power itself, apparently.

It's your money, but people don't seem to understand that often
spending an extra 40 bucks or so on a GOOD power supply can
save a complete rebuild, costing hundreds of bucks. -Dave

Actually, I'm sure the power supply he bought from the
store is perfectly fine. Don't forget about "power good"!
If the power supply doesn't see this, it will not stay on.

You've got that backwards, its PROVIDED by the
power supply, not observed by the power supply.

That is how all ATX power supplies are designed,

Nope.

and it is indeed built-in component protection. If anything is shorting
out (as could very well be the case here, since his first power supply
fried something), it will shut down a working power supply.

Different issue entirely to the power good line.