Shut down my PC, unplugged it, moved it to new location. Plugged it back in and it would not power up green light on the ASUS P4P800SE would not stay lite. Replaced power supply, green light on the mother board will now stay lite, but when the power button is pushed the three lights on the front tower will flash for a second and then go dim, green light on the motherboard remains green.

try disconnecting the lower optical drive and rebooting...may just be a bad drive.

HI

it is a SMPS problem. SMPS is the main power supply it is also known as smart module power supply..

if you want to check try this link



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regards'
sandy

there are many things that can shut down a motherboard.
power spikes, the caps on the board, a blown diode, voltage regulators alot of people use a power strip to protect there computers which is wrong they will not prevent a spike from getting to your hardware, even tho the light comes on the board (3.3v) if you do not have 12v or 5v getting through the board theres no way to get it to go the only thing you can do is see if you can find someone who fix's the boards or upgrade to a new mobo or find a replacment on ebay or one of the other sites

follow this procedure:
1. unplug the ac adapter and keep it unplugged.
2. Remove the battery and keep the battery unplugged.
3. Hold the power button down for 15-20 seconds(Nothing will appear on the display and none of the lights will light up)
4. Release the power button and plug in the ac adapter ONLY. (A power indicator light should be lit on the ac adapter when it is plugged in)
5. Normally power on the notebook.
6. If the unit does not power on, remove the ac adapter and insert the battery into the system.
7. Plug the ac adapter back into the system, the battery charging indicator light will light up. If the battery indicator light does not light up, the ac adapter may not be providing proper power to the unit, and may need to be replaced.

Char S.

once check the ram and keep it in other slot and check it .clean the ram and keep it

Try this troubleshooting guide it has worked for me in the past 99% of the time http://arstechnica.com/guides/tweaks/troubleshooting.ars

dont u dare ever use 220 line on thes eon usa power u blow it ever time u turn it on at 220 v dont u dare do that not no reset switch erther u must now buy new power supllly ok

if its by the power button the led just indicates power after u have removed its source and reconnected it........this is normal nothing to worry about.

Remove the power supply after everything is unplugged and take it to your nearest electronics store. They should have a tester there. This is probably the problem.

Try a few things for me OK? From what you typed, turned on the psu "the toggle switch on the psu", pc seemed to be starting up. I need you to keep the toggle switch on the power supply in the on position. Press and hold the start button on the PC case to shut it down. Give it a few seconds & power up by pressing the power switch on the case. Notice a differance? Next, unplug everything connected to the pc expect the monitor, mouse & keyboard. Try to boot. Still no? Remove the side of the case exposing the board. Turn the psu off by flipping the toggle switch on the psu, wait till the green light on the board goes out. Grab the Mb ( I know it's tight in there) and see if you can move the board in any direction. Not loose? Re-check all data & power connections for a solid connect. Re-check your case to Mb connections. Also check the PSU, there is a red slide switch it should be set to 115v. Post your findings..
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