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[newindian]

hi experts !

when I start my computer at the begining of the day, it does not send any signal to the screen, nothing happens, the power light of the screen just blinks, then I have to open the tower and remove everything like hard drive, cd-drive, cmos battery and even the bios reset plug ( I can't remember the technical name for it ) then I have to power it " on ", It might give the beep codes or not mostly. Then I have to put all the things back in again and then it would boot, so what could be the reason, the motherboard fitted right now is a replacement by a repair shop, another point noticed here is that, if there is a cd kept in the cd drive or even if I power on the modem before the computer, then also this problem can happen, however once the computer is in use for some time and then I reboot it, it comes on fine ususally. please guide.

 

[PCBONEZ]

Please do not make duplicate posts for the same problem.
It makes the topic hard to follow.
I think you can delete the other one in this forum. Please do so if it will let you.
~~~~~

What is the motherboard?
What is the power supply?
Do you know how to use a volt meter and do you have one.
When it fails to start what do the lights on the tower do?
When it fails to start do the fans spin? ... Do they 'kick' and then stop?
When it fails to start do the drives spin-up?
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[wcogent]

it's possible that
1) your board is grounded. fix the insulation
2) your cd drive is broken and is shorting out the system. disconnect before turning on.

 

[PCBONEZ]

I would agree were it not for the fact it runs after messing with it a bit.

If it's stone dead when it's dead then possibly +5vsb is drifting too low in soft-off or the PSU is otherwise screwy.

If it's doing the ole 'fan kick' though, there may be a partially shorted cap [or caps] somewhere preventing voltages from 'coming up'.
- When you hit the switch the caps have ~ 50 milliseconds to charge to about 80% of their nominal voltage. When they get there the Chipset issues the PWRGD signal to the PSU. If the PSU doesn't get the signal within ~ 50 milliseconds it kicks back off to protect the motherboard. It's a safety feature required by the ATX specs. [The actual numbers vary with which spec you are looking at.]
When the PSU kicks on for ~50 milliseconds then kicks back off -> fan kick.
A marginal cap could get enough charge while he's playing with it [trying to start it repeatedly] to put it 'over the hump' allowing the system to start.
-
A dead chipset will also cause the fan kick but this board runs sometimes so that isn't it.

Many also be some nVidia based board which can mean BGA problems that can be intermittent.
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[Strider]

the motherboard fitted right now is a replacement by a repair shop

Are you having these startup problems even after replacing the motherboard?

- When you hit the switch the caps have ~ 50 milliseconds to charge to about 80% of their nominal voltage. When they get there the Chipset issues the PWRGD signal to the PSU. If the PSU doesn't get the signal within ~ 50 milliseconds it kicks back off to protect the motherboard. It's a safety feature required by the ATX specs. [The actual numbers vary with which spec you are looking at.]

Thanks mate; didn't know this.

 

[PCBONEZ]

You're welcome.
I was an electronics tech [control systems for nuclear plants] for many years before I got into computers. Sometime in the late 90's I decided to combine the two skills.
- Without getting long winded..
I come at computer problems from a different perspective than most techs.
I like to find WHY the motherboard isn't working.
Once I know that as often as not they can be fixed.
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[Comptronic]

Oh, I know a lot you don't know...

But until you get more experienced moderators I won't be here to share it.

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Could you please private message me? I'm trying to message you and I'm not able to send you a private message.