help! Only the LED on mobo is on but could not boot

  • Thread starter Thread starter rc
  • Start date Start date
R

rc

Hi guys,

I am building a new pc by my own. It is ASUS p4p8000 motherboard and PIV
2.6 FSB 800 CPU, Two 512MB RAM. Now I am facing a problem. When I power
on the PC, only the LED on the motherboard is light but there is nother
else happened. The CPU and chassis fans are not running, no display on
the monitor, even no sound of the cpu and HD. Could anyone give me some
hint what is the problem?

Thanks!

Berc
 
rc said:
Hi guys,

I am building a new pc by my own. It is ASUS p4p8000 motherboard and PIV
2.6 FSB 800 CPU, Two 512MB RAM. Now I am facing a problem. When I power
on the PC, only the LED on the motherboard is light but there is nother
else happened. The CPU and chassis fans are not running, no display on
the monitor, even no sound of the cpu and HD. Could anyone give me some
hint what is the problem?
Click to expand...

What power button are you using to turn it on?

LED on mainboard should (usually) be on whenever the PC is plugged into the
wall and PSU turned on, whether or not the PC is turned on.

Bad power supply would be my first guess... You don't mention a video card,
yet you say there's nothing on the monitor. Obviously you haven't told us
everything yet.

Try PSU, mainboard, CPU & heatsink, video card and memory ... NOT in the
case and nothing else attached.
 
I am building a new pc by my own. It is ASUS p4p8000 motherboard and PIV
2.6 FSB 800 CPU, Two 512MB RAM. Now I am facing a problem. When I power
on the PC, only the LED on the motherboard is light but there is nother
else happened. The CPU and chassis fans are not running, no display on
the monitor, even no sound of the cpu and HD. Could anyone give me some
hint what is the problem?
Click to expand...

When you say powered on the PC , I might assume that you turned on the power
supply. The ATX computers will have a switch on the case that you must
press that shorts two pins on the motherboard while the switch is pressed.
Did you install this connector correctly ?
The power sypply is not normally turned off but supplies a small ammount of
power to the motehrboard to detect this switch and also so the keyboard or
mouse can be used to turn the system on.
 
Phrederick said:
What power button are you using to turn it on?

LED on mainboard should (usually) be on whenever the PC is plugged into the
wall and PSU turned on, whether or not the PC is turned on.

Bad power supply would be my first guess... You don't mention a video card,
yet you say there's nothing on the monitor. Obviously you haven't told us
everything yet.

Try PSU, mainboard, CPU & heatsink, video card and memory ... NOT in the
case and nothing else attached.
Click to expand...

Hi, Actually now the problem seems that the psu is on but the power of
the case does not do anything. I push the power butten on and the
motherboard led is on. And when I push the power of case on, nothing
happened. The case is ANTEC sonata and the psu is also from antec, 380w.
Seems not a bad brand. Vedio card is attached, it's a Sapphare ATi 9600
256MB one. The memory is two 512 twinmos PC 3200. Which locate in two A
slot on the motherboard. I have unplugged everything and plug them back
again to have a try, but still. :-(. Anyway, there is one guess is about
keyboard. Since now I have not attached a keyboard with the computer (I
am looking for a normal PS2 one, only a wireless one with me now.) I
will see what will happened after that althought I don't believe the
problem is coming from keyboard.

Thanks for your advice!
 
Ralph Mowery said:
When you say powered on the PC , I might assume that you turned on the power
supply. The ATX computers will have a switch on the case that you must
press that shorts two pins on the motherboard while the switch is pressed.
Did you install this connector correctly ?
The power sypply is not normally turned off but supplies a small ammount of
power to the motehrboard to detect this switch and also so the keyboard or
mouse can be used to turn the system on.
Click to expand...

Hi,

When the power of psu is on , the LED is on. And then I push the power
of the frant panel to start the pc, but nothing happened . That's the
situation. I have trid with the pw switch line which connect between the
power butten on the front panel and the slot on the mainboard wich
diffrent position.(I mean positive and negative lines). Actuall this is
also the problem I thought. But after I tried several times with that, I
think maybe it is not the case. Or, the connection is broken. Since the
case is not a bad one, in this moment I would assume the connection is
ok.
 
Take the Power Switch connector off the mother board. Replace it with the
reset switch connector. Push the reset switch and see if it comes on. This
should eliminate the Power Switch as a possible problem. If it comes on, the
power switch is bad.
 
MrB said:
Take the Power Switch connector off the mother board. Replace it with the
reset switch connector. Push the reset switch and see if it comes on. This
should eliminate the Power Switch as a possible problem. If it comes on, the
power switch is bad.
Click to expand...
The power switch is not polarity sensitive it is just like a light
switch and does nothing more than close a circuit, so if the if you
have placed the connector on the proper pins and the machine does not
come on than I would suspect a bad switch or more likely you are not
getting the proper voltage from the power supply, or the power supply
is not compatible with your new CPU.
So maybe bad power supply or not the proper power supply.
 
Back
Top