Question about HP ATX-300-12Z (ATX30012ZBD) 300-Watt Power Supply

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Power supply light has blinking green light

When the computer is plugged into the wall outlet and is powered down, there is a clicking noise and the green light on the power supply is blinking.

Does this mean that the power supply is bad?
Is there a reset button, switch or fuse somewhere ?

Please advise.....

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Re: power supply light has blinking green light

If the power box is bad, The computer will not come on. if you only get a green light, you would need to start with replaceing the power box, if you get a new one and the same thing happens, then the mother board is bad too.

Posted on Nov 27, 2007

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Re: power supply light has blinking green light

After researching on the web I replaced the power supply. Problem solved.

Posted on Feb 13, 2008

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When the computer is plugged there is a fast blinking green light and will not turn on

A fast blinking green light means the power supply is bad and will have to be replaced. Make sure you replace it with a least the same wattage supply that is in it now.
Hope this helps.

Feb 10, 2011 | HP ATX-300-12Z (ATX30012ZBD) 300-Watt...

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My Bestec ATX-300-Z cannot power up. When try to power it up after unplugging from wall outlet, it quickly show green led and the led goes off. I unplugged every connection to the computer, yet it cannot...

I may be wrong, but, seeing that it is only a 250watt power supply, its was probably cheap. NEVER buy cheap power supplies for PC's. Weak PS's can cause damage to multiple components on a computer.

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Hi there PSU Stopped working. Dismantled and found fuse blown. Replaced with new fuse, which blew straight away. Any ideas as most likely component that has failed / needs replacing?! Regards,...

Follow these steps :
Power on your computer and place one hand behind the power supply's fan on the back side of the computer case. Check to see if there is any air being blown by the fan and listen for any fan noise, which will both indicate the power supply is still receiving electricity. Turn off the computer.
Remove the power cable from the current wall outlet it is plugged into and connect it to a different outlet to make sure the outlet isn't the cause of the problem. Replace the power cable entirely with a new one and plug it into the original wall outlet to find out if the cable was defective.
Power on the computer and check to see if the problem still persists. Turn the computer off if you are still having problems and disconnect all of the cords from the back of the case. Set the computer down onto its right side on any nearby stable work surface. Unlock the left side panel from the computer by removing the two case screws on the back end of the case. Push down on the panel slightly and then slide it away from you to remove it from the case.
Make a visual inspection of the power supply, which will be located at the top left side of the case. Check to see if the power supply has sustained any obvious physical damage such as from spilled liquid or possibly falling out of the drive bay. Replace the power supply if there is any obvious physical damage.
Check the connections of the IDE cable that run from the motherboard to the power supply. Make sure the connection is secure at both sides and hasn't slipped out. Replace the IDE cable with a new one if it has any obvious physical damage.
Unplug the cord that runs from the power supply to the hard drive. Turn on your digital multimeter and set it to the "DC" setting. Attach the power cable back into the power supply with the case still open. Press the computer's power button.
A Digital MultimeterInsert the multimeter's black probe into the black wire of the power supply cable you removed from the hard drive. Take the multimeter's red probe and plug it into the yellow wire of the power supply cable. Check the reading that appears on the digital multimeter's screen.
Replace the power supply if the reading on the multimeter is lower than 11 or higher than 13.

Oct 24, 2010 | Apple FW800 (661-2816) Power Supply

1 Answer

Emachines w3507 power

detarch all accessories or hardware connected to the system , then bring out the power pack itself out completely look for a soldering led to test the functionality of the power pack itself if it rotates the fan of its pack by looping the first hole to the third hole cable in the power pack connector that will head into the motherboard. therefore, check the mother board if there is any damage on it like some component if all this is false . then plug the power pack to the outlet and fix the connector of the power pack to the motherboard after detaching both cd drive , floopy disk drive leaving the hard disk and the memory . then change the memory card and press on the system there should be a solution from all this . the problem should be from the Memory not to be able to start up the system but go through those process i have given you before concluding it was the memory ok....

kindly rate this solution......

May 05, 2010 | E-Machines Bestec ATX-300-12E Rev. D 300w...

1 Answer

My power supply is blinking green light and my PC has no power

plug your pc directly to your wall outlet and see if it turns on. If it works, then the problem is your power supply. If power supply has a reset button, press it and try again. If pc does not turn on when plugged to wall outlet, then power supply for pc may be out.

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2 Answers

Asus ac adapter will not wrk green light on adapter

First check the wall socket make sure you are getting power, plug a lamp into it for instance. If there is no green light on the adapter then it is bad and you will need to order a new one from your computer manufactor.

rate with 4 diamonds

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Flashing Green Light on Power BESTEC Power Supply

This is an easy fix so here you go nice and simple:

Problem: Your motherboard circuit has been cut.

Causes: Power disconnected during operation. Power outage or short in the surge protector.

Symptoms: Flashing green light on both motherboard and power supply. System will not power on.


Step 1: Ensure that both the power supply and the motherboard lights are flashing green, not solid or off.
Step 2: While the power is on, disconnect the power supply from the motherboard. This connection is the largest of the connections and should be listed as the 'P1' or 'Primary' power connection.

Step 3: Wait until the green light on the motherboard stops flashing and check to ensure that the green light on the power supply is now solid. If it is not solid, disconnect the power to the power supply and wait until the light turns off completely. Then reconnect, it should be solid now.

Step 4: While the power is on, reconnect the P1 connection to the motherboard and you should now see that the light on the motherboard is solid.

Step 5: Power on your PC. The problem should not persist.

Warnings: If the power supply light remains flashing after you have restored power to it while it is disconnected from the motherboard, it may be a system failure in the power supply itself requiring replacement. Always be careful when working with an active or live power machine.

I hope this helped! Good luck!

Jun 23, 2008 | Bestec (ATX-250-12E) 250-Watt Power Supply

1 Answer

450 power supply

The cd may be bad, or if the power supply is just marginal, it may be failing when the cd motor spins up.

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