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Thread ID: 102471 2009-08-20 05:12:00 New PSU and motherboard boochild (11733) Press F1
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802839 2009-08-20 05:12:00 I would appreciate some assistance . First time for re-building my PC . Capacitor blow on previous MB, so have replaced the PSU, MB, CPU, ram and video card . Re-assembled in the case -( I know, I know, would have saved a great deal of effort had I tested it first before putting it back in) . Now it won't power up at all . No led on MB . No nothing .

I am sitting here at work thinking of the possibilities - incorrectly connected power lead (don't think so checked several times), faulty PSU (brand new - possible though), MB issue (hope not - but again possible) .

What else could it be? How should I diagnose the issue?

Thanks for your help
boochild (11733)
802840 2009-08-20 05:17:00 You sure you have got the power switch connected to the correct two pins on the motherboard?
You said it yourself too, take everything out of the case again and test on the bench with just motherboard & CPU, RAM, PSU & video card if not onboard.
CYaBro (73)
802841 2009-08-20 05:19:00 Are the front panel connectors plugged into the right pins - sounds like its not getting the signal to fire up.

Have a look at the manual that comes with the board , remove all the front panel connectors, find the two pins that say PWR, take a flat bladed screw driver, and touch the two PWR pins - it should boot up.

If it doesn't - the board could be shorting on a riser / case. Even if the 4 pin Power connection to the CPU is not plugged in, you should get some fan activity.

DONT laugh - but is it actually plugged into the wall, turned on, and plugged into the PC and that turned on as well --- seen people say " of course it F**** is -- turn on the power and it works. -- it happens.
wainuitech (129)
802842 2009-08-20 05:26:00 DONT laugh - but is it actually plugged into the wall, turned on, and plugged into the PC and that turned on as well --- seen people say " of course it F**** is -- turn on the power and it works. -- it happens.

Had this today. Chap picked up a PC I'd fixed, took it home, plugged it in, hit the power button and nothing happened. He called up... "...you fixed this computer, it still doesn't f***** go, I want you to come out and sort the f***** thing out..."

I asked if he'd double checked all the plugs were in tightly and it was turned off at the wall. The response I got was.. "I'm not f***** stupid...*long pause*..."

*in the background* "Who the f*** switched off the power point?!?. Never mind, it's going now..."*click*.

:lol:
wratterus (105)
802843 2009-08-20 05:39:00 Thanks for your quick response .

Yes plugged in and turned on . Re-seated power cable several times, and changed wall socket . :)
boochild (11733)
802844 2009-08-20 05:44:00 Front panel connectors - a real possibility. It mention in the manual to ensure the correct polarity - how do I check this? there are no marking on the plug nor the connection. Am I missing something? boochild (11733)
802845 2009-08-20 05:52:00 Try shorting out the necessary pins with a screwdriver. (That's all the power button does anyway, just in a more civilized manner.) wratterus (105)
802846 2009-08-20 05:56:00 The power button does not need to go any special way. Only the LEDs themselves need to go around the correct way

Make sure it's plugged onto the right pins though

What motherboard do you have? Does it have a standby LED on it? (Asus boards usually do) This will at least prove your PSU is supplying power to the board.

If it does not turn on at all, something might be shorted. Make sure you don't have any parts of the I/O Shield stuck in the USB ports or any motherboard mounting spacers in the wrong place
Agent_24 (57)
802847 2009-08-20 06:11:00 Gigabyte GA-MA785GM-US2H . Will double check on LED. And will try shorting the pins in hope. Definite possibility spacer issue so will check that too.
Thanks for all the help
boochild (11733)
802848 2009-08-20 06:16:00 It mention in the manual to ensure the correct polarity - how do I check this?

Usually the wires from the case - the coloured wire is Positive and the white or black is ground .
The diagram in the manual shows + positive and - ground .
pctek (84)
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