PC can't boot/start, cpu fan won't work

[Link97]

Hi,

(I really don't know where to post this,feel free to move the thread if necessary)

Yesterday i noticed that my cpu fan wasn't working anymore so unplugged it to clean it (thermalright fan+heatsink). When i did that, i turned the psu off with its very own power button.

Then i plugged the fan back on the mobo, turned the psu on. The fan started spinning for a second, and then the whole computer was starting to turn itself on, just for a second, then turning itself off immediatly for a sec, then turning on, then off...etc


So, i unplugged the gpu (r9280x OC- sapphire), and the computer is working again (using it right now so i think that's not the cpu). But not that cpu fan, it's still not spinning even after plugging it to the second cpufan port.

I had the same issue with another sapphire gpu, a radeon hd5850, it was preventing the computer to boot/switch on/launch windows. But when i removed that 5850, fans where alright, everything was normal. (That was with that same psu)

So I REALLY don't know what to do since i can't try another hardware in my rig or try my hardware in another rig. I'm suspecting the psu but what if it's the mobo? What if it's the gpu AGAIN? What if it's a gpu issue caused by a faulty psu?

Can someone provide me some help and advice please?

I also had strange issues recently with a mouse (cooler master storm sentinel advance 2), it was faulty despite being 1month old (rma'd it, the new one works fine). I also had 2 old odd that stopped working and causing issues in Explorer. So maybe is that cpu fan issue a coincidence, but i think not. Something is terribly wrong in my rig.


Btw the rig is:
Msi z87-g45
R9 280x OC
8gb kingston ram (it's not faulty i believe, 'been testing it with memtest some weeks ago)
Antec hcg 520w
2 hdds (Western Digital (1tb) & Hitachi (500gb), both 7200rpm)

There are 3 big case fans plugged to sysfans ports on the mobo.

Nb: http://puu.sh/oXETj/d6cc8ff534.png a screenshot of hwmonitor, i wonder if something is wrong with the voltages.

 

[Shaun o]

Basically most motherboards in the bios have a fan speed detection mode.
The rpm speed can be set in the bios of for example the cpu fan.
If the motherboard detects that the fan is spinning bellow the lowest set value in rpm for the fan alarm.


Two things will happen the system may beep and ask you to check the cpu fan on a power up of the system and a error of cpu fan error is displayed.

Or it will simply shut the system down after a few seconds when the main power button on the system is pressed.

I dare say it`s this due to the cpu fan as you say not spinning.

Check the fan connector to see if it is three or four pin.
Or if there are 3, 4 wires running from the cpu fan to the connector.

Verify that when connected to a fan header of the motherboard if it uses a 3,4 pin type connector.
Making sure the pins line up from the fan connector to the fan header.

You may have a snapped or broken wire on the fan where it is soldered to the PCB of the fan.

To check it you will have to remove, or unscrew the fan from the cooler and flip it over.
Or replace the fan with another one if you have one to screw, or clip to the cpu heat sink.

Connect it up to the fan header of the motherboard and see if the system stays powered on.

Let me know how you got on and if it cured your problem.
If not will have a think on the other causes it may be.
Link ok.

 

[Link97]

Thanks a lot for your reply!

I checked the fan speed in the bios: it says "0"rpm, and no matter if i set the speed on 25 or 100%, it's still not spinning. I regularly hear a little weird noise (every 5 sec i think), it's the fan trying to start, but it looks like it just... can't. Maybe is it really faulty, but after what happened with the boot issues and the gpu, i don't think that's a coincidence. Mobo or psu or something else is causing issues.

Two things will happen the system may beep and ask you to check the cpu fan on a power up of the system and a error of cpu fan error is displayed.

My beeper/speaker never beeped, i don't know why.

I'm gonna try what you told me asap, and see if i can try the default intel heatsink too, then i'll post here what happened.

 

[Link97]

Well, well, well. I've been plugging the old intel heatsink to "cpufan2" port. It works fine. Then i plugged the supposedly dead Thermalright fan to a "sysfan" port, leaving both "cpufan" ports empty. And guess what? It's working.

It's spinning at 1355rpm according to Speedfan.

This is bringing even more questions now, i still wonder if it's a faulty mobo or psu.

For some weird reasons i feel like windows was launching itself kindah... fast, same with some apps right after typing my password. Maybe is it because i just shut the computer down or i'm going even more paranoid.

Haven't tried putting the GPU back for now, it's insanely dusty and i need to buy a compressed air can.

 

[Link97]

I just partially cleaned the gpu (its heatsink is less dusty but still dusty) and it went back in my rig. Plugged my third case fan directly to psu since the motherboard fan port is now used by the cpu fan.

The pc is working.

But it's not over, i'm worried by what happened and i still think that "something" is not fixed.