Power Green Light Flashing HP Desk Top PC m7250n
During a power outage their is a surge when power come back on the grid (surge can be caused by lighting strikes akso). This surge trips the internal procters inside the power supply to protect the Mother Board, hard drive, processor and fans and any device that pulls wattage from the power supply. Since all these power using devices are trying to pull power at the same time to boot the computer back up one ends up with a loop of surge thrugh the power supply with a protective trip, reset, surge again and trip again. This will continue in this loop as the computer is trying to boot all the devices at one time (Mobo, Hd, processor, cooling fans and other devices). Simoly, more power wattage is being demanded than the protectors will allow at one time causing a protective shutdown followed by a restart followe by a protective shutdown in a continious loop.
The normall sequence for a boot is to boot the board, processor and fans followed by a boot of the hard drive, and other boot devices once the board is energised, NOT all devices at the same time, as this results in an overload and trips the protectors. This protective loop is indicated by the blinking light as the power is turned on and then shut down for protection as the wattage pull is over the demand that the protectors will allow.
Blinking light indictes you are in the protective loop.
SOLUTION: 1. Disconnect the Mother Board connector, with the computer unplugged, this will allow the power supply to reset at maximum wattage upon reboot.
2. Disconnect the Hard Drive power connector and ay boot device power supply cables, this will allow the Mother Board, processors and fans to boot without an overload of the protector inside the power supply.
3. Plug in the computer and the indicator light will be solid green indicating that it is reset and out of the loop.
4. With the computer pluged in and the Power Supply fully energised, plug in the Mother Board. The computer will now boot, and the processor fan will come on and the cooling fans.
5. After computer has rebooted, shut the computer back down and connect the Hard Drive power cable and any other power cablis that were unplugged.
6. Reboot with all cables connected and you are up and running again.
POWER SUPPLIES HAVE AN INDICATOR LIGHT FOR A REASON.
REMBER - BLINKING LIGHT IS AN OVERLOAD OF THE PROTECTORS AND ELLIMINATING THE OVERLOAD SOLVES THE PROBLEM AND THAT THE POWER SUPPLY IS WORKING AND CONVERTING POWER.
NO LIGHT MEANS NO POWER OUTPUT AND THAT INDICATES THE POWER SUPPLY IS NOT FUNCTIONING AND NEEDS REPLACED.
Hope this helps everone with power outages and lightining strikes. It is a rather common problem and can also occure when building a computer and one missmatches the power supply with the board wattage needs. If the board wattage needs are greater than the power supply output you will get stuck in a potective loop eventually. WHEN BUILDING A COMPUTER ALWAYS MAKE SURE THE POWER SUPPLY CAN PRODUCE MORE WATTAGE THAN YOU CAN CONSUME AT THE MAXAMUM LOAD.
Have a great computing experiense.
Jan 13, 2008 |
HP Media Center m7250n (ED842AA) PC...