PC power up

  • Thread starter Thread starter stupar
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stupar

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Ok guys this has been a bit of a head scratchier form me.
Having just built an upgraded system for some reason it wont power on the conventional way I. E pressing the power button on the case.
What I have found though is if I press the little red power button on the motherboard itself the PC comes to life.
Is this a BIOS thing that needs to be changed to allow proper power on?
The board I'm using is an asus P5Q-E Intel p45 based chipset.
Any help would be most welcome.
 
neil_g said:
youve definately got the power button connected the right pins on the motherboard?
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Definitely, double checked against the manual and everything, diagrams and all.
 
neil_g said:
no worries. i cant see anything in the manual for that board for a bios setting so i would imagine its a hardware thang.
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That was my thinking because all I could see in the manual was about advanced power management (APM) and sleep/hibernation modes.

Will disconnect the pins and reseat them see if that helps.

When you say short with a paperclip do you mean touch the two power button terminals on the board with the clip?
 
Yep, short across the two pins to make a connection, which is what the switch on the case is doing when you press it. For maximum reliability and least motherboard frying potential don't electrically connect yourself to the paper lip, so hold it with something insulating. Sometimes it looks like it doesn't work because you are sinking some current so it isn't going via the board. If that works then it just a dodgy case switch, if not then its a motherboard problem.
 
stupar said:
When you say short with a paperclip do you mean touch the two power button terminals on the board with the clip?
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Yes. All the power switch does is make the connection to tell the power supply to switch on.
 
I'd use a terminal screwdriver to short the pins or a short piece of wire with the ends stripped back just a little.

Maybe also check there is nothing touching the back of the board and causing a short?
 
im pretty sure the power switch pins will only be 5v as the case switch is a low current jobby * i hold no responsibility for you electricuting yourself :D

you should only need to touch them briefly also, power switches arent latching these days.
 
Have you tried swapping the reset button & power button connections so that the PC should turn on by pressing the reset switch? (just to eliminate the power switch itself)
 
RobertP said:
I'd use a terminal screwdriver to short the pins or a short piece of wire with the ends stripped back just a little.

Maybe also check there is nothing touching the back of the board and causing a short?
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Ironically the power button and reset buttons don't work but the hard drive light and mobile speaker work fine.

If there was a short on the board would that not prevent the PC from posting and booting?
 
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2blue4u said:
And don't take what the manual says as gospel.
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Hmmmmm........will have a fiddle tonight. The case connections go into a long white plug which in turn plugs into the mobo. Think I will remove this and plug straight into the board just incase the white adaptor is the problem.
 
neil_g said:
trouble is asus dont (or at least my p8p67-m doesnt) have them labelled on the board as you have the really handy block you plug everything into then plug that into the board, so you have to trust the manual..
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Precisely! Without that little white block I would have been lost, will do like for like from the block to the board and thus rule out the block as the issue.
 
Have you checked the BIOS to make sure it's all set the way you want it?

My computer is set up so that just turning on the power to the computer switches it on or touching a keyboard key after it has been switched off by Windows etc.

.
 
Try building the PC without the components in the case. You'll still have to short the power switch jumpers but this rules out any issues with the motherboard shorting itself against anything in the case.

To see if it boots you don't need the hard drive in place, just the motherboard, power supply and memory. (Graphics card if it isn't built-in, of course) You should at least get something on the screen.
 
petersmart said:
Have you checked the BIOS to make sure it's all set the way you want it?

My computer is set up so that just turning on the power to the computer switches it on or touching a keyboard key after it has been switched off by Windows etc.

.
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PhotoMonty said:
Try building the PC without the components in the case. You'll still have to short the power switch jumpers but this rules out any issues with the motherboard shorting itself against anything in the case.

The board supports advanced power management so that would be an option if all else fails.

To see if it boots you don't need the hard drive in place, just the motherboard, power supply and memory. (Graphics card if it isn't built-in, of course) You should at least get something on the screen.
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Cheers, advice taken on board
 
Ok, problem fixed!
Turns out the power switch on the case is faulty but the reset button does work, so for the time being I have the reset switch plugged into the power slot on the board.

Cheers for all your help folks :thumbs:
 
stupar said:
Ok, problem fixed!
Turns out the power switch on the case is faulty but the reset button does work, so for the time being I have the reset switch plugged into the power slot on the board.

Cheers for all your help folks :thumbs:
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Good stuff, well good in that you know what it is :D
 
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