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PC power won't turn on

By test2k11
Jun 20, 2011
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  1. Earlier today, the PC turned on fine. Then I shut down, turned the switch button off on the back of the computer case. Later I switched the plug back on, pressed the Power Button, but there was no indication of anything. No power, no light, no fan running.

    I tried open the case to check, I saw the Power button light is "ON" on the motherboard. So I don't think it's the motherboard problem. I check the wire cable from the Power Button to the motherboard, everything is fine. I even unplug the Power Button cable and re-plug them back into the motherboard. Still not on. :(

    Anyone has any idea or clue as to why it can't be turn on? I really don't want to buy another PSU or motherboard until I get enough clue. :( Thank you.
     
  2. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    What's the make and model of this PC? Does it have a green LED on the back of the power supply? How old is the computer?
     
  3. test2k11

    test2k11 TS Rookie Topic Starter

    NO

    It's a self-built PC. So I customize on a lot of things. I have ThermalFlake Toughpower 750watt. Mother board is Asus P6T Deluxe.

    I'm not quite sure understanding what you mean by green light on Power Supply. My Power Supply never had any light led. But if the Power Supply is bad, then Motherboard light wouldn't turn on when I plug the switch on.


    I've built it for 3 years now. Quite honestly, I suspect it's the front panel Power Button is damaged. If that the case, does it mean I need to buy a new Case? I really LOVE this case, the build, stylish, and convenience of these button location. It's $100 case.
     
  4. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    Just because the green light is on the motherboard doesn't mean that the power supply is good, it just means that the 5 volts is present. There are many other voltages needed.To check the front power button, short the two pins where the power switch connects to the motherboard momentarily and the PC should power up. Some cheap power supplies have a green led near the power plug socket
     
  5. test2k11

    test2k11 TS Rookie Topic Starter

    yes

    What do you mean to short the two pins where the power switch connects to the motherboard? You mean to take unplug the 2 pins and re-plug them back in? I did that before but still no use.

    Thanks for helping. I'll try to switch Power Supply to another PC. If it doesn't work, I don't know what to do. :( Been spending the whole day fixing this thing.
     
  6. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    "You mean to take unplug the 2 pins and re-plug them back in?"...

    NO! Unplug the connector that goes to the front panel power switch. Take a paperclip and momentarily touch the 2 pins where the power switch connector goes on the motherboard. This will start up a good computer. Do it a few times to get the hang of it. It won't hurt anything, and it will save time
     
  7. test2k11

    test2k11 TS Rookie Topic Starter

    Should I do this while connecting the power plug and everything turn on OR turn everything off firs (unplug the power, switch P/S off, etc.)

    Also should I insert the paper clip into the two Power Switch +/- at the same time while pressing the power on button or doing it separately?
     
  8. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    "Also should I insert the paper clip into the two Power Switch +/- at the same time while pressing the power on button or doing it separately?"...

    You do not have to do anything with the power switch. It is disconnected if you are doing this right. Just plug in the computer and momentarily touch the 2 pins where the the power switch connects to the motherboard at the same time, with the paperclip. The computer should start up
     
  9. test2k11

    test2k11 TS Rookie Topic Starter

    I did that but nothing seem to happen. Computer is still not turn on?

    What I did was bend the paper clip into parallel point and touch the 2 pins POWER SWITCH on the motherboard. Am I doing this right? What if after doing that and it still not turning on? Is it the Power Supply problem? or the Motherboard battery is dead? If motherboard battery is dead, then why am I getting light on the motherboard (POWER BUTTON and RESET BUTTON).
     
  10. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    You touch the 2 pins and immediately remove the paperclip. If the computer won't start, the power supply is the first thing to try. It could be the motherboard, but only after you try another power supply... The light on the motherboard only means that +5 volts is present. A computer needs +5, -5, +12, +3 volts and a voltage sense logic level to operate. A bad CMOS battery might cause loss of bios settings and loss of date and time settings. It doesn't usually cause a computer not to start
     
  11. skipper86

    skipper86 TS Rookie Posts: 19

    you need a good technician man...!!
     
     
  12. test2k11

    test2k11 TS Rookie Topic Starter

    Okay, I think it might be the PSU because I put PSU into another computer to test and that test computer can't power on as well. I'm ordering a new PSU 775Watts Thermoflake Tough Power XT series to see if a new one can power it on.

    Thank for you helps.
     
  13. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    A new power supply will do the job I'm sure. Keep us posted :)
     


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