J
JAD
PSu or MB. Since you have the MB 'all is good lite', I'm thinking PSu is not delivering on
one of the rails.
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PSu or MB. Since you have the MB 'all is good lite', I'm thinking PSu is not delivering on
one of the rails.
V
Vanguard
BertieBigBollox wrote ...
You could tell by looking. With the PSU connected to the mobo, power
up and check if the CPU fan starts a bit. You could also give it a
spin with your fingers to check if the blades rotate freely. You
won't know until you look inside. I thought you said you already
replaced the PSU with a new one so I figured you had the computer to
look at.
Dont know which fan. Like I said its a friends PC and I can get any
sense. They said the fan was very noisy so its probably the PSU fan
I
guess - there is no case fan.
So, I suppose it could just be a dead CPU fan?
You could tell by looking. With the PSU connected to the mobo, power
up and check if the CPU fan starts a bit. You could also give it a
spin with your fingers to check if the blades rotate freely. You
won't know until you look inside. I thought you said you already
replaced the PSU with a new one so I figured you had the computer to
look at.
B
BertieBigBollox
PSu or MB. Since you have the MB 'all is good lite', I'm thinking PSu is not delivering on
one of the rails.
Yes. Original PSU is knackered but still the same with new PSU. So I
think its PSU and mobo.
B
BertieBigBollox
You could tell by looking. With the PSU connected to the mobo, power
up and check if the CPU fan starts a bit. You could also give it a
spin with your fingers to check if the blades rotate freely. You
won't know until you look inside. I thought you said you already
replaced the PSU with a new one so I figured you had the computer to
look at.
Not a spark out of anything except for the LED on the mobo.
V
Vanguard
BertieBigBollox wrote ...
Under the following conditions:
- PSU's 20- or 24-pin connector is *not* connected to the motherboard.
- PS-ON (green wire) shorted to ground (black wire) in the 20- or
24-pin connector.
- A working hard drive is connected to a power tap to provide a load
on the PSU.
Did you then:
- See the fan inside the PSU spin up?
- Hear the hard disk spin up?
- Measure the 5V and 12V wires on the power tap used for the hard
disk?
Under the following minimal hardware setup:
- Remove all daughtercards from slots leaving only one video card
installed.
- Remove all memory except for one stick.
- Remove all but one hard disk.
- Disconnect removable drives (floppy, CD/DVD, Zip).
- All case fans disconnected (you have the side panel removed at this
time).
- 20- or 24-pin connector from PSU connected to header on motherboard.
Did you then:
- See the system power up?
- See any jitter of movement by the CPU, chipset, or any other fan?
- See if the PSU's fan spinning?
- Hear the hard drive spin up?
Check if the Power or Reset switches are defective. Remove the wires
for both the Power and Reset button switches from the header pins on
the motherboard. If there is no white ink printing on the motherboard
to denote which pins are for what function, write down to which pins
the wires went. Then temporarily short across the 2-pin Pwr header on
the motherboard to emulate the momentary switching for the Power
button. You might be able to use a jumper to do the shorting (there
might be one hanging on the CMOS reset pins that you could use). If
it powers up now, one or both of the case switches for Power or Reset
are defective. Check if the buttons above the switches are damaged.
Could be they got smacked and are stuck in.
Not a spark out of anything except for the LED on the mobo.
Under the following conditions:
- PSU's 20- or 24-pin connector is *not* connected to the motherboard.
- PS-ON (green wire) shorted to ground (black wire) in the 20- or
24-pin connector.
- A working hard drive is connected to a power tap to provide a load
on the PSU.
Did you then:
- See the fan inside the PSU spin up?
- Hear the hard disk spin up?
- Measure the 5V and 12V wires on the power tap used for the hard
disk?
Under the following minimal hardware setup:
- Remove all daughtercards from slots leaving only one video card
installed.
- Remove all memory except for one stick.
- Remove all but one hard disk.
- Disconnect removable drives (floppy, CD/DVD, Zip).
- All case fans disconnected (you have the side panel removed at this
time).
- 20- or 24-pin connector from PSU connected to header on motherboard.
Did you then:
- See the system power up?
- See any jitter of movement by the CPU, chipset, or any other fan?
- See if the PSU's fan spinning?
- Hear the hard drive spin up?
Check if the Power or Reset switches are defective. Remove the wires
for both the Power and Reset button switches from the header pins on
the motherboard. If there is no white ink printing on the motherboard
to denote which pins are for what function, write down to which pins
the wires went. Then temporarily short across the 2-pin Pwr header on
the motherboard to emulate the momentary switching for the Power
button. You might be able to use a jumper to do the shorting (there
might be one hanging on the CMOS reset pins that you could use). If
it powers up now, one or both of the case switches for Power or Reset
are defective. Check if the buttons above the switches are damaged.
Could be they got smacked and are stuck in.
B
BertieBigBollox
Under the following conditions:
- PSU's 20- or 24-pin connector is *not* connected to the motherboard.
- PS-ON (green wire) shorted to ground (black wire) in the 20- or
24-pin connector.
- A working hard drive is connected to a power tap to provide a load
on the PSU.
Did you then:
- See the fan inside the PSU spin up?
- Hear the hard disk spin up?
- Measure the 5V and 12V wires on the power tap used for the hard
disk?
Yes.
Under the following minimal hardware setup:
- Remove all daughtercards from slots leaving only one video card
installed.
- Remove all memory except for one stick.
- Remove all but one hard disk.
- Disconnect removable drives (floppy, CD/DVD, Zip).
- All case fans disconnected (you have the side panel removed at this
time).
- 20- or 24-pin connector from PSU connected to header on motherboard.
Did you then:
- See the system power up?
- See any jitter of movement by the CPU, chipset, or any other fan?
- See if the PSU's fan spinning?
- Hear the hard drive spin up?
Nothing except light on mobo. BTW - theres also a square 12v mobo
connector from the PSU.
Check if the Power or Reset switches are defective. Remove the wires
for both the Power and Reset button switches from the header pins on
the motherboard. If there is no white ink printing on the motherboard
to denote which pins are for what function, write down to which pins
the wires went. Then temporarily short across the 2-pin Pwr header on
the motherboard to emulate the momentary switching for the Power
button. You might be able to use a jumper to do the shorting (there
might be one hanging on the CMOS reset pins that you could use). If
it powers up now, one or both of the case switches for Power or Reset
are defective. Check if the buttons above the switches are damaged.
Could be they got smacked and are stuck in.
Tries this too. Still nothing...
V
Vanguard
BertieBigBollox wrote in message
The the PSU is okay.
You probably have a mobo with a 20-pin connector for the PSU. The PSU
is made to support a mobo with either a 20- or 24-pin connector.
Check the header pins on the mobo for the CPU. See if there is 12V
there. If not, that would explain why the CPU fan doesn't spin. In
that case, you might start hunting for a replacement mobo. Unless you
have another mobo that uses the same type of CPU, you won't be able to
tell if it is the mobo or CPU that is broken. You could get another
mobo that takes the same CPU but it is likely, at that point, that you
would be upgrading to a better CPU and better mobo.
Yes.
The the PSU is okay.
Nothing except light on mobo. BTW - theres also a square 12v mobo
connector from the PSU.
You probably have a mobo with a 20-pin connector for the PSU. The PSU
is made to support a mobo with either a 20- or 24-pin connector.
Tries this too. Still nothing...
Check the header pins on the mobo for the CPU. See if there is 12V
there. If not, that would explain why the CPU fan doesn't spin. In
that case, you might start hunting for a replacement mobo. Unless you
have another mobo that uses the same type of CPU, you won't be able to
tell if it is the mobo or CPU that is broken. You could get another
mobo that takes the same CPU but it is likely, at that point, that you
would be upgrading to a better CPU and better mobo.
P
ProfGene
It could also be the CPU. I had a motherboard that I could never get toPower LED on mobo comes on but nothing when you hit the power button.
Can I assume the mobo is dead?
Also, just to rule out a power button problem, is it acceptable to
short (with a jumper) the two-pin power button header on the mobo to
force a power on that way?
work but after about three or four years I bought a CPU that it liked
and it started to work.
R
Roy Collingwood
Yes, I keep a short lead with a push-button on the end for testing m;boards
without having to fit into a case
to switch on, you can short the connector, but do not leave it shorted.
Roy
without having to fit into a case
to switch on, you can short the connector, but do not leave it shorted.
Roy
P
ProfGene
You can never assume anything. I had a motherboard that never didProfGene said:It could also be the CPU. I had a motherboard that I could never get to
work but after about three or four years I bought a CPU that it liked
and it started to work.
anything until one day I tried a different processor and it suddenly
worked. Try removing the RAM and booting. It should then if it is
working beep a number of times however many the warning is for that MB
that there is no RAM. If it does then you will know something in it is
working. Have you tried removing most of the cards to the bare minimum
and booting?
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