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Power supply problem

I'm having problems that I'm pretty sure are related to my power supply.

I installed a new dvd burner in my system. The system booted up fine. It recognized the DVD player and installed it. It told me that I had to reboot the system to complete the installation. I rebooted it and it worked fine for about 5 minutes. After about 5 minutes after reboot the system shut off just like I unplugged the computer. I was standing near the computer but not actually using it while this happened.

The computer has not booted since. If you push the on switch, absolutely nothing happens. I have unpluged and repluged the computer into several different plugs. I bought a new more powerful power supply and installed it but the system is still dead. There is a light on the motherboard and there is a light which goes on and off as I turn the computer on and off with the dsl plug. So it appears that I am getting power. I returned the new power supply and got another. And the exact same thing happens with the 3rd power supply.

I had the exact same systems happened when I got the computer 2 years ago. The original power supply failed, I installed a second, when I brought it to a shop they installed a third power supply and told me that the power supply I purchased was bad.

This all started when I installed a new DVD burner. Since the system booted, installed the DVD player and then rebooted sucessfully, I doubt that there was any problems with the DVD installation. I could have overloaded the old power supply.

Is there anything else I can check?

My motherboard is an ASUS A7n8x-e Deluxe

Reply to
scenario_dave
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Disconnect the new DVD drive and see what happens. If system runs normally, return the DVD drive. If still dead, your system motherboard is likely bad. Cheers!!

--
Dave M
MasonDG44 at comcast dot net  (Just substitute the appropriate characters in the 
address)

Some days you're the dog, some days the hydrant.
Reply to
DaveM

I've tried unplugging all of the harddrives, dvd players and floppy directly from the board. Nothing happens when I push the on switch. I don't hear the fan start or anything. I haven't unplugged any of the cards yet.

When you install a power supply, does anything else plug into the motherboard besides the 20pin plug, or are there any reset switches on the MB etc. ? My MB is about 3 years old so as far as I know I dont need the new extra 4 pins that come with my power supply. I've double/triple checked the 110/220 switch and the on/off switch on the power supply. The only other thing on the power supply itself are the plugs that plug into the MB and components.

The thing that confuses me is that I had the exact same thing happen when I first installed the board about 3 years ago. The tech told me that the replacement power supply that I installed was faulty and he installed a third one and it worked. I'm wondering if there was some other step I missed when I installed the power supply? Since if its the power supply problem, I've bought 3 bad power supplies in addition to the two that went bad. If its not the power supply, why am I getting exactly the same symptoms on the same MB a second time?

Art wrote:

Reply to
scenario_dave

Try this and try that and.... well that list is long and still does not say what is wrong. You want to identify the problem now, and then fix it. In but minutes with a 3.5 digit multimeter, we can identify the problem AND then replace the suspect. Do not attach or disconnect anything. Changing things may even exponentially complicate the problem. That 3.5 digit meter is available for less than $20 in Sears, Lowes, K-mart, Radio Shack, and Home Depot. That's the complex part.

With computer plugged into AC receptacle, use meter to measure voltage on purple wire between power supply and motherboard (connect probes to purple wire by pushing into nylon connector and other probe to chassis). That voltage must be more than 4.87 VDC. If not, power supply controller will not tell power supply to power on. Next measure voltage on green wire. It must be more than 2 volts before switch is pressed and must drop immediately to less than 0.8 volts when switch is pressed. This tells power supply to turn on.

Next measure voltage on gray wire. It must rise to more than 2.4 volts within seconds after power switch is pressed. Again, you want to see what happens when switch is pressed - not just long after switch is pressed. This signal tells motherboard that power supply is OK.

If gray wire is good or bad, then move on to one red, orange, and yellow wires. Measure each as switch is pressed. Within one second, each should exceed 3.23, 4.87, or 11.7 volts DC. If any does not rise, then find what ever on motherboard or peripherals is excessively loading that voltage.

Not > I've tried unplugging all of the harddrives, dvd players and floppy

Reply to
w_tom

Thank you for the detailed instructions. I'll try them tomorrow if I get a chance and post the results. I read a few other post that suggested using a meter but most of them did not give anywhere as clear instructions on how to as you have.:)

I was kinda hoping that I'd forgotten or didn't know about an instillation step. I've had that happen in the past, forgot to plug the computer in sort of errors.

I was plann> Try this and try that and.... well that list is long and still does

Reply to
scenario_dave

There are so many wires and connectors in front of the connection between the power supply and the MB that I'll have to disconnect some of them to get to it.

Reply to
scenario_dave

Hi...

One more suggestion, for what little it may be worth...

Take a good look, make sure that you haven't accidentally partially dis-lodged one of the cards in your machine while you were installing the dvd. AGP cards are particularly susceptible to being not fully seated, and weird things result.

Take care.

Ken

Reply to
Ken Weitzel

Is it an Antec power supply? I've seen a lot of them die like that, I just replaced my own with an Enermax recently after the Antec started randomly shutting off.

Reply to
James Sweet

Unplug the cards, I had my graphics card come partially unseated once and the system wouldn't power up.

Reply to
James Sweet

No, not from the motherboard. Unplug the *power connector* going from the power supply to each of your drive devices. Is your PSU fan spinning?

Make sure none of the cards are shorting to each other.

Reply to
UCLAN

So do you still have the same intermittent. The system may work fine for a while, then do some strange things. Even with a new supply, one then repeats those same measurement in but a few minutes to so that margin voltages today do not result in intermittet crashes next week.

Reply to
w_tom

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