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Question

My computer will power up but not boot

Sep 9, 2016 3:55AM PDT

I recently changed my motherboard. When I plug everything in the GPU and the case fans spin, the motherboard LEDs light up but the PC won't start and the CPU fan will not spin. I'd appreciate any help and thanks in advance.

Discussion is locked

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Clarification Request
Header
Sep 9, 2016 4:29PM PDT

OK guys it turns out that the problem isn't the fan, it's the header because my old fan which works perfectly fine on other computer won't work on this one

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Answer
what is the computer make and model?
Sep 9, 2016 4:34AM PDT

You may have to reinstall windows on top of itself. Each model motherboard has different chips on it controlling everything and they need particular drivers, so when you do a motherboard change it's often easier to just reinstall windows on itself. Just be sure to NOT let it format the drive first.

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(NT) Do I have to install the same version that I used before
Sep 9, 2016 6:19AM PDT
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Answer
Cpu fan
Sep 9, 2016 6:27AM PDT

Unplug hdd's/optical/gpu/ram.
You don't need any of that stuff for the cpu fan to spin.

I'll assume the fan does work and you plugged it into the proper header.

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Cpu fan
Sep 9, 2016 6:42AM PDT

The fan did work yesterday and it's plugged into the proper header. I unplugged ram, hdd's etc. but it still doesn't work

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Cpu fan
Sep 9, 2016 7:03AM PDT

Take the mobo out of the case and set it on a piece of card board.
Connect the psu to the mobo.
Nothing else connected.
Locate the power switch pins on the mobo and short them for a second.
Does the cpu fan spin?

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It still doesn't
Sep 9, 2016 7:46AM PDT

But that's not my biggest problem right now if I have to replace it I can

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Cpu fan
Sep 9, 2016 7:57AM PDT

Remove the cpu.
Plug the fan into the header.
Power it up.
Does the fan spin?

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No
Sep 9, 2016 8:33AM PDT

I removed the CPU and plugged the fan into the header. When I powered up the computer the fan still didn't spin.

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Picture
Sep 9, 2016 3:16PM PDT

If I have the picture right your down to 3 parts....psu/mobo/fan...nothing else.
If you have another fan test with it.
If your old mobo still works test with it.

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My old mobo
Sep 9, 2016 4:25PM PDT

Sadly doesn't work actually that was the reason I replaced it

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Answer
I am curious,
Sep 9, 2016 4:16PM PDT

without the CPU fan being on, that cpu should get very hot to the touch very quickly...does it? If not, then it means the cpu isn't on which means the PSU shouldn't be on either.

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The CPU
Sep 9, 2016 4:24PM PDT

Does heat up quickly so I'm guessing it works properly, I think I'll try the crappy fan that comes with the CPU and maybe the problem is just the CPU heating up (not likely but trying won't hurt)

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No,
Sep 10, 2016 10:09AM PDT

you issue now is the fan, you have to find out what cause that. Is it the fan, the connector/motherboard, etc.?

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Answer
LET"S COVER A BASIC MOTHERBOARD CHANGE GAFFE
Sep 9, 2016 4:33PM PDT

It happens so many times it's not funny. The old board is out and the owner installs the new board.

But wait, not working. When we hear this we pull the board and see if there are any extra mounting posts where there should not be. Hopefully the new board is not fried.

You left out the exact details of old, new, CPU model, every detail.

I would check the motherboard support list and if getting no where, pull the motherboard out of the case for a cardboard test.

Remember the details are missing. For example I have no reason to tell you to plug in the ATX12V connection.