Plugging in the power supply, the mobo LED light inside becomes lit. I hit the power button and the power LED light becomes lit but nothing else kicks in (fans, HDs, bios, etc.). There's a "Test Switch" on the power supply so I pressed it and held it in and the computer boots up normally as long as I keep my finger on the switch. If I were to let go, everything but the power LED light and the mobo LED light goes off. Say I hit the power button for 5 seconds to shut it off. Now when I hit the "Test Switch", the CPU fan and the power supply fan turn on but, of course, the HD and everything else won't because the power button wasn't hit. There are 5 wires coming from the power button area. Three wires are coming from to the dual-color power LED (green/red for standy mode). The other two come from the power button switch. The opposite end of the wires go to the motherboard grouped together.
It seems that the power supply is operating fine when I hit the test switch on its side. This must mean that the mobo isn't signaling the power supply to power up when the power button is hit. I can't imagine the power button being bad because the LED does light up when the button is depressed. Does anyone have any ideas what could be wrong?
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Re: power LED on but no boot up
I'm wondering if you have the jumpers set for the power button correctly on the motherboard. If the test switch is working properly when held in, then there's something wrong with the power button itself (maybe it's not going in enough to turn it on? I've had that problem before and had to McGuyver it with super glue and a little wad of paper to work correctly)
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The fans and indicators working for a sec would normally mean that your power supply is Ok. This flash of current must trigger a switch in the mobo to start the boot process. This is not happening. The RAM is a principal player here if it does not connect the memory to the processor nothing will happen. Assuming the RAM is correct and has worked faultlessly before, remove and clean the teeth with an eraser. This prob can also be caused by the VGA card not connecting. Usually alarms sound if your mobo speaker is connected but that depends on each mobo. These are basic steps that usually start machines that have been inactive for a time or have recently been exposed to high humidity. There could be other faults...............
In this order: check PSU is working ( fans run in the psu), test with another psu installed, See of there is a green LED lit on the mobo Check capacitors are not bulging or leaking and there are no signs of burned circuit traces on mobo remove ram and try booting see if you get power to the cpu fan try bypassing the PW switch and touching the PW terminals on the fpanel header to eliminate swith problem.
It seems like you have bad MOBO. I recently ordered all the stuff to build 2 new systems. Built the first one, no power, just like yours. Moved everything to the 2nd MOBO, everything worked. I did a RMA on the DOA MOBO. Got the new one and it fired right up. Sometimes you just get bad stuff.
I have built quite a few PCs and I have often found the same problem when trying to boot for the first time. An old trick that might help is to repeatedly energize then drain the PC electricity. Do this by plugging in the PC momentarily then unplugging it then immediately pressing the power button on the PC while there is no power hooked up. Do this several times over and over again in quick succession. Finally turning on the PC with the power connected. If the power supply on the PC has a switch on it you may use that instead of actually plugging and unplugging. Also you might try pressing and holding down the "ins" or "insert" key while powering on the PC. Hope this helps.
KingPin, is there any sign of life at all? Any lights, whiring, harddisk spinning?? Is there an LED (small light) visible on the motherboard when the power is on???
If nothing, certainly a power problem - but where. While you have the case open looking for the lit LED on the mobo, can you see any capacitors, the little cylinder-type components on the mobo circuit board that look like little batteries standing up, there'll be about half a dozen of them, that look like they may be bloated, or like a coke can left in the freezer about to explode. Do any of these capacitors look like they could be oozing goo, maybe a yellowish rusting liquid. If any do, this is not good.
If none of that applies the next step is to check your power supply. I would not suggest an amateur to do this over a step-by-step chat as it involves shorting out points and if the system is live, the wrong points shorted, well, guess you'd know what could happen (not good). The power supply is not easy to diagnos for errors, they're tricky buggers that can test well for voltage but once a load is put on them they roll over and play dead. Get an expert to test your power supply, very simple task of they plugging in a PSU tester (or borrow one, or buy one).
Please keep us informed on how you go - seriously, we grow stronger as we grow wiser when we finish a job.
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it could be your power switch, veriy that it isnt the power supply by
1.) un-plug it from the main board
2.) look at the main board connector(one coming of the power supply)
3.) you should see green wire and next to it a black one
4.) using a paper clip bridge the too wires
5.) if it works proceed to net step if not get a new power supply
to check case switch and board switch
1.) plug in power supply to main board
2.) look at the pins where the power button connects to
3.) using a metal object (blade screw driver) bridge the pins
if the board should start up>
then its your power button on the case that is bad, you can try to repair it, chage it or buy a new case,
if it doesnt work.
1.) ensure that jcms(jumper to flash the bios) is set correctly
2.) unjack each drive one at a time to see if any is causing stalling
3.) get a new main board
So if i'm getting this correctly your computer will not boot even with just the basics. Have you tried directly shorting the pins on the mobo instead of using the power button? Unlikely problem but it would be an easy fix. You might also want to take your power supply out and get it tested. The geek squad at best buy will usually do that for free, or you can buy your own tester, or buy a cheap power supply. If both the switch and power supply are good and you get nothing trying to start it up it means you probably have a bad mobo. If your memory or cpu was bad and nothing else it would still boot up just without anything on the screen and might give you a series of beeps. Well I hope i've helped and that you can get this fixed soon.