All 3 case fans quit working...wtf?

[Andy22]

Ok, so my computer shut off the other day. After opening the case I see that my 3 case fans are no longer spinning. The CPU fan spins just fine and the system still powers up but quickly seems to over heat. I assume this is why it shuts off. I have tried running different power leads to each fan but they just don't spin. I tried a power lead that was plugged into the DVD drive that works...no spin. So the PS works enough to spin the mobo and other peripherals and cpu. All 3 fans couldn't have gone out at once right? Any ideas? I wouldn't think it would overheat that quickly (10-15 minutes) since the cpu fan is still working. The temp gets up to about 45C.

Any ideas?

 

[DirkGently1]

Perhaps there was a power surge and the fans just happen to be the least resiliant componants in your PC?

Kinda odd, isn't it?

 

[KGB]

With the system OFF, take your finger and try to spin the suspect fans. Do they feel like the bearings/bushings are binding?

Regarding the simultaneous failure question: if they are the same brand/model and age, yup!

 

[pete1229]

It is more then likely a PSU issue. The DVD/CD drives run on the 5v rail while the case fans run on a 12v rail. It's possible the 12v rail that powers the molex cables has failed You would need a PSU tester or a voltmeter to test the 12v rail of those molex connectors to determine if it has failed, if so then it's time for a new power supply. I agree with you, the possibility that all three fans failed at exactly the same time seems slim regardless of the fact they are the same age and manufacturer. Btw the 12v wires are yellow.

 

[Andy22]

Thanks for the feedback...I have an old system and will take a fan out of it that I know is working and see if it works. if it doesn't then I guess it's time to shop for a PS...first time in about 10 years I can remember having ANY type of hardware failure so I guess I was due.

 

[pete1229]

What is the PSU you have now? I would try the reverse, take one of the fans out of your newer rig and connect it to the PS in your older system, that will tell you for sure. If the fan spins up, then you'll know if its a bad 12v rail in the newer pc's PSU.

 

[Andy22]

What is the PSU you have now? I would try the reverse, take one of the fans out of your newer rig and connect it to the PS in your older system, that will tell you for sure. If the fan spins up, then you'll know if its a bad 12v rail in the newer pc's PSU.

Good call, I'll do that. It's a 450 watt cpu, don't remember the brand but it's only about 1 1/2 years old.

 

[denis280]

What is the PSU you have now? I would try the reverse, take one of the fans out of your newer rig and connect it to the PS in your older system, that will tell you for sure. If the fan spins up, then you'll know if its a bad 12v rail in the newer pc's PSU.

I suspect the psu myself.pretty sure i would put my hand in fire if im wrong.

 

[Germonicus]

Try removing each fan in turn,might be a bad fan affecting the mobo fan controller/power.

Always better to take a component out of a faulty system and try it on a known working one as Pete suggests.If the PSU is what fragged the fans then adding a known working fan to that system could easily result in another non-working fan.

 

[pete1229]

I doubt the fans are connected to the mobo... "I tried a power lead that was plugged into the DVD drive that works...no spin" ... (OP) I believe they were/are connected via molex, which would then indicate a psu and not a mobo issue.

 

[Modelworks]

If the fans do not work when connected to a working drive connector they are bad. PC fans use a very low end switching circuit that has next to no redundancy or protection built into them. A quick surge is all it takes to kill one or ten if they are on the same rails.

 

[pete1229]

Andy, how did it work out did you fix the problem?

 

[Germonicus]

Andy, how did it work out did you fix the problem?

It's not lookin' good is it Pete?