Flash - pop - bad smell..........oh,oh.

[waltinvt]

My standby computer blew what I thought was just the power supply but I just installed a brand new one and absolutely no response.

Well practically no response - a tiny green light on the mother board lights up right where the large 24 (in my case 20) pin harness plugs in. Other than that I can get nothing.

I've quadriple checked the connections, made sure everything's tight.

The switch at PS is on and passing power to at least that tiny green LED on the MB.

I've checked the wires to the front power on / reset switches and made sure everything else is tight on the MB.

I'm wondering if when the PS went, it blew something on the MB but if so, it's not something that I can see evidence of.

I'm not a computer geek (as many of you know), so any help would be greatly appreciated.

 

[rockymtnhigh]

I suspect it blew your motherboard when the powersupply went. Happened to my wife's computer in December. Hell, it killed not only her motherboard, but her Hard Drive as well.

Mine had the same deal -- the green light was on, but nobody was home.

I also tried just replacing the power supply initially.

I decided that it was just cheaper to buy her a new computer then to rebuild. Well, maybe not cheaper, but more convenient.

If you go the route to replace the MB, you will want to first make sure that the RAM and HDD are still ok.

Ticks me off that there is no sort of "circuit breaker" on a power supply, so when it goes, it just shuts down, instead of taking out the whole stinking thing....

 

[Bulldog]

My standby computer blew what I thought was just the power supply but I just installed a brand new one and absolutely no response.

Well practically no response - a tiny green light on the mother board lights up right where the large 24 (in my case 20) pin harness plugs in. Other than that I can get nothing.

I've quadriple checked the connections, made sure everything's tight.

The switch at PS is on and passing power to at least that tiny green LED on the MB.

I've checked the wires to the front power on / reset switches and made sure everything else is tight on the MB.

I'm wondering if when the PS went, it blew something on the MB but if so, it's not something that I can see evidence of.

I'm not a computer geek (as many of you know), so any help would be greatly appreciated.

Did you check the input power slide switch on the power supply to make sure it is not set to 220V?

I purchased a power supply few years back for a higher wattage type (450), and it of course came from Taiwan, but I had a similar problem of no turn on, and that's what it was; It came in with the slider switch set for 220 volts input.

I know that not everything is that simple to fix as that, but take a look.

 

[rockymtnhigh]

Did you check the input power slide switch on the power supply to make sure it is not set to 220V?

I purchased a power supply few years back for a higher wattage type (450), and it of course came from Taiwan, but I had a similar problem of no turn on, and that's what it was; It came in with the slider switch set for 220 volts input.

I know that not everything is that simple to fix as that, but take a look.

I had that happen once


But sadly, I doubt it is that simple.

 

[diogen]

Does the PS fan start?
If not, and the PS is new, the mobo is toast.

Have you had all components connected?
When troubleshouting, connect just the mobo to the PS, nothing else.
I had a HD go bad first and take the PS with it a bit later. Trying to figure out what was wrong, I blew another PS...

Diogen.

 

[pacman]

Yup, this happened to my 2nd (kids) computer last week. I replaced the power supply and it still wouldn't power up. I just happened to have an extra motherboard (the same exact one) and installed that and it booted right up.

 

[waltinvt]

Ticks me off that there is no sort of "circuit breaker" on a power supply, so when it goes, it just shuts down, instead of taking out the whole stinking thing....

but that would make too much sense and cut down on related repairs.

 

[waltinvt]

Did you check the input power slide switch on the power supply to make sure it is not set to 220V?

I purchased a power supply few years back for a higher wattage type (450), and it of course came from Taiwan, but I had a similar problem of no turn on, and that's what it was; It came in with the slider switch set for 220 volts input.

I know that not everything is that simple to fix as that, but take a look.

I'm no geek but I did manage to check that one

 

[waltinvt]

Does the PS fan start?
If not, and the PS is new, the mobo is toast.

Have you had all components connected?
When troubleshouting, connect just the mobo to the PS, nothing else.
I had a HD go bad first and take the PS with it a bit later. Trying to figure out what was wrong, I blew another PS...

Diogen.

No PS fan - no nuttin - just the little green light and yes, the PS is brand new. It cost me $70 + S&H too. Antec MP-400. My mb is only 20 pin so I did have to disengage the 4 end pins like they recommend.

Now why doesn't the fan in the PS power up since that's getting power before it even goes to the mb?

 

[waltinvt]

Yup, this happened to my 2nd (kids) computer last week. I replaced the power supply and it still wouldn't power up. I just happened to have an extra motherboard (the same exact one) and installed that and it booted right up.

I can just see me trying to swap an mb. Either me or it would probably go out the window

 

[rockymtnhigh]

I can just see me trying to swap an mb. Either me or it would probably go out the window

Hopefully there will be a bush or something to cushion your fall.

 

[diogen]

Now why doesn't the fan in the PS power up since that's getting power before it even goes to the mb?

I'm sorry for the stupid question, but you do have the power switch pair cable connected to the appropriate mobo pins, right?

If yes, the PS fan doesn't start because there is no signal from the mobo, i.e. the mobo is dead.

Diogen.

 

[jayn_j]

Ticks me off that there is no sort of "circuit breaker" on a power supply, so when it goes, it just shuts down, instead of taking out the whole stinking thing....

The electrical engineer's dictionary defines an FET as an electrical device that instantaneously fails in order to protect a fuse.

In these days of high speed electronics, the fuse always blows after the circuit has failed. About the only thing is accomplishes is preventing thermal runaway on transformers, thus preventing a fire (a worthy goal)

 

[rockymtnhigh]

The electrical engineer's dictionary defines an FET as an electrical device that instantaneously fails in order to protect a fuse.

In these days of high speed electronics, the fuse always blows after the circuit has failed. About the only thing is accomplishes is preventing thermal runaway on transformers, thus preventing a fire (a worthy goal)

Ah... so you are saying what I think would be a bright idea actually isn't feasible, rather then part of an evil conspiracy betwen Antec and the Mobo manufacturers...

 

[waltinvt]

I'm sorry for the stupid question, but you do have the power switch pair cable connected to the appropriate mobo pins, right?

If yes, the PS fan doesn't start because there is no signal from the mobo, i.e. the mobo is dead.

Diogen.

Please don't consider ANY question stupid when it comes to me and computers. I'm a classic case of knowing just enough to be dangerous.

However my kids think I'm a computer hero since they get my office hand-me-downs and I manage to keep their games working for them. I hate to disappoint the one that's waiting in the wings for this one.

With the exception of having to adjust the main harness from 24 pin to 20, I think I have everything else hooked up just like the old PS, including the 4 pin, yellow / black wired plug that's at about 7oclock from the CPU on the mb - which I believe is the power - right?

 

[diogen]

Not what I meant.
There are a bunch of thin wires going from the case buttons: power led, reset, HD led, speaker, etc.
One of them is Power Switch.
It has to be connected to a particular pin pair on the mobo, just where all the other wires go.
Without it the PC will behave just like you describe...

Diogen.

 

[jayn_j]

Not what I meant.
There are a bunch of thin wires going from the case buttons: power led, reset, HD led, speaker, etc.
One of them is Power Switch.
It has to be connected to a particular pin pair on the mobo, just where all the other wires go.
Without it the PC will behave just like you describe...

Diogen.

There are also 2-3 cables from the power supply to the MB. You only speak of the big 2x pin one. Did you connect the others as well?

 

[navychop]

This is why I only use PC Power & Cooling power supplies. When they fail, which is very rare, they do not take the motherboard with them. I've lost too many computers at work to cheap power supplies.

 

[rockymtnhigh]

This is why I only use PC Power & Cooling power supplies. When they fail, which is very rare, they do not take the motherboard with them. I've lost too many computers at work to cheap power supplies.

Good to know they are a good brand; I thought Antec was, but have now had problems with two Power Supplies from them...

 

[diogen]

There are also 2-3 cables from the power supply to the MB. You only speak of the big 2x pin one. Did you connect the others as well?

Main power (20-24 pin), additional power (4 pin) and sometimes the PS fan speed contol.
The rest is peripherals...

Diogen.