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?
Its the Mother Board..I had the same problem and had to have a new MB put in
Posted on Dec 04, 2007
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)
Posted on Mar 22, 2007
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ever happen to anyone?
thanks for the suggestion. i know the switch is fully functional; i've tested it independently. as an experiment, i've also took the PS_ON signal from the power supply and connected it to ground and watched it power up just fine. (i've also tested the power supply by using it in another computer) The only way I could get it this PC to fully work is by hooking up a transistor to connect the PS_ON signal (to the collector/drain), ground (to the emitter/source), and the wire going to the power on LED in front of the case (to the base/gate). That way, when the power button is pushed, the motherboard sends the signal to light up the front LED (which it originally did) and, at the same time, send a signal to the transistor to bring the PS_ON signal to ground. When the PS_ON signal is grounded, the power supply activates all of its power lines going to the components like the hard drive and stuff and the computer boots up fine (which is what i experimented with earlier).
i agree...it is the motherboard..the only way i was able to reuse the motherboard was to buy a PNP transistor and wire stuff up from the power supply to the motherboard...crazy and not recommended
yes i have the same problem. This hhappened when i switvhed cases from the stock to a cooler master case. I plugged everything in correctly and the screws on the motherboard arent too tight. When i start the computer teh fans go off for a split second and dies. I know that my mother board works b/c when i switch cases back to the stock case it boots. Plz help
I have a similar problem with my Gateway. I really do not know that much about computers. If this fixable, or should I just get a new motherboard?
INSIDE motherboard led works power up don't work
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