pauldonson
asked on
New build PC - CPU fan spins for a second then stops
Having spent an afternoon trying to solve this problem I gather it is a fairly common problem but it is DRIVING ME MAD!!!
From the beginning:
I am building a new PC with the following:
Asus P5LD2-VM DH motherboard
Intel (775) Pentium 4 3.4 GHz processor
512MB DDR2 RAM
600W EZCool power supply
(The rest is irrelevant because I can't get it to POST so far!)
When I power on, the CPU fan spins for about 1 second and then stops, the motherboard power light remains on at all times.
Now for the interesting part:
I have tried the CPU, power supply and memory with another motherboard (Asus P5B) and sometimes the same problem occurs but sometimes it does seem to boot up - the problem is that with this motherboard (which doesn't have onboard graphics) as soon as I plug in a PCI-E graphics card the CPU fan spins for one second and then stops!
I have tried a different power supply, different memory with both motherboards and seem to be getting the same problem. The only thing that I haven't replaced is the CPU and CPU fan.
I have taken the motherboard out of the case (to check for shorts), reset the CMOS and STILL the problem persists.
Does anyone have any ideas? I don't want to have to buy a new CPU unless I know for certain it is that (I have spent a fortune on this already!!)
It is a PC for my boss so 500 points to whoever helps me fix it!
From the beginning:
I am building a new PC with the following:
Asus P5LD2-VM DH motherboard
Intel (775) Pentium 4 3.4 GHz processor
512MB DDR2 RAM
600W EZCool power supply
(The rest is irrelevant because I can't get it to POST so far!)
When I power on, the CPU fan spins for about 1 second and then stops, the motherboard power light remains on at all times.
Now for the interesting part:
I have tried the CPU, power supply and memory with another motherboard (Asus P5B) and sometimes the same problem occurs but sometimes it does seem to boot up - the problem is that with this motherboard (which doesn't have onboard graphics) as soon as I plug in a PCI-E graphics card the CPU fan spins for one second and then stops!
I have tried a different power supply, different memory with both motherboards and seem to be getting the same problem. The only thing that I haven't replaced is the CPU and CPU fan.
I have taken the motherboard out of the case (to check for shorts), reset the CMOS and STILL the problem persists.
Does anyone have any ideas? I don't want to have to buy a new CPU unless I know for certain it is that (I have spent a fortune on this already!!)
It is a PC for my boss so 500 points to whoever helps me fix it!
ASKER CERTIFIED SOLUTION
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also trying powering up the computer with no other devices attached other than the motherboard, ram, processor and power supply... remove all cards and drives from the system. Double check and verify the power switch setting on the back of power supply that it's not 220 instead of 115 or whatever is applicable where you are.
I know this is simple, but I have to ask. You *did* connect the little four-pin P4 12V connector, right? I'm only asking because what you're describing is exactly what happens if you forget to plug it in.
and try with another video card, even an old PCI one will do
ASKER
I can't believe it was that simple! It was indeed a faulty power switch - I shorted the pins as you suggested txpaulrs.
This probably explains the random behaviour as well.
BIG THANKS!!!
Thanks for your input as well nobus and thoffman.
This probably explains the random behaviour as well.
BIG THANKS!!!
Thanks for your input as well nobus and thoffman.