New PSU - Case fans remain lit after PC shutdown

e36Adz

e36Adz

e36Adz

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I've just replaced my 700W OCZ power supply with a Corsair RM1000 which I picked up from the MM. That's the only thing that has been changed in my system recently.

Previously, when I would shut down my PC, the lights on my keyboard and mouse would remain on and this seemed normal. The led on the front of the fan controller would also remain lit. I've installed the new power supply and it seems to be working great however, after shutting down the system, all my case fans (6 of them) remain lit although they are quite dim. They are not spinning, the system has definitely shut down but the leds are still on and this seems a bit odd. Can this damage the fans? Is it normal??

I am going to try a different connector on the PSU and then a different cable. Anyone had this before?

As I said, the PSU seems to be working just fine. Just wondering if the above is something I should be concerned about.
 
try plugging one of the fans into the motherboard headers directly and see if the issues remain

suspect it could be a dodgy molex cable / connector on the psu :eek:
 
Hi mate, it was in a HAF- X and the front fan is LED lit, directly into the Molex connector from the PSU and no issues here. Funny that your fan controller also remains powered ?
Shouldn't everything shut off & power down ?
I doubt it is the PSU as I had no issues with it connected via Molex to the LED fan, does it close down eventually (minutes) or does it stay for hours?


I have an older system and the mouse also stays lit, that is with an old Corsair HX unit
 
Update:

I shutdown my PC and switched OFF the PSU from the back of the tower. The fan led lights remain ON. After 5 minutes of waiting, the fan lights are still ON.

I've opened the case and tried different ports on the PSU and when I unplug the cable from PSU, the fan lights go off, but as soon as I plug it back into the PSU (tried all the ports) the fan lights come back ON. This is all while the PSU is switched OFF from the back.
 
ademcg said:
Hi mate, it was in a HAF- X and the front fan is LED lit, directly into the Molex connector from the PSU and no issues here. Funny that your fan controller also remains powered ?
Shouldn't everything shut off & power down ?
I doubt it is the PSU as I had no issues with it connected via Molex to the LED fan, does it close down eventually (minutes) or does it stay for hours?


I have an older system and the mouse also stays lit, that is with an old Corsair HX unit
Click to expand...

Hi mate, hoping I do get to the bottom of it but the only thing that has been changed is the PSU.

The only thing I can think of trying now is a different cable. As mentioned though, after shutting down the system, all case fans remain lit even when left overnight. Previously it was just the front led on my fan controller and my keyboard/mouse which remained lit after shutting down.

Even more bizarrely, after switching off the PSU from the switch at the back, the fans lights are still ON!?! :confused:
 
e36Adz said:
Hi mate, hoping I do get to the bottom of it but the only thing that has been changed is the PSU.

The only thing I can think of trying now is a different cable. As mentioned though, after shutting down the system, all case fans remain lit even when left overnight. Previously it was just the front led on my fan controller and my keyboard/mouse which remained lit after shutting down.

Even more bizarrely, after switching off the PSU from the switch at the back, the fans lights are still ON!?! :confused:
Click to expand...

Sounds like there is something which is staying live continuously. that is controlled by the motherboard, not the PSU as it is the Motherboard which "requests" the power from the PSU, not the other way around.

Have you google foo'd ? I found the link below but that was only a quick search.

http://windowsforum.com/threads/fans-keep-running-after-shutdown.183332/

Also I guess there is the Corsair forums ?
Ade

Edit:
Failing that we can get in touch with Corsair Technical Support.

Is there any power settings in your Bios of the motherboard?
 
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So, if you turn the PSU off at the switch on the back the LED's stay on.
What happens if you physically unplug the PSU? Do they still stay on?
 
Yes they still stay on, even when unplugging the psu. The only time they go off is when I remove the molex cable from the psu which powers the fan controller. All the fans are plugged into the fan controller, not into the motherboard.

As I've said, the only thing I've changed it the psu. With the old psu this wasn't happening, only the led on the fan controller at the front of the tower would remain lit.
 
It sounds like something is back feeding then. If your PSU is unplugged and these lights are staying on then the power has to be coming from somewhere.

Have you tried flicking the CMOS battery out and unplugging the PSU from the wall?
Something is powering those LED's and there isn't really anywhere for a PC to "store" power.
 
Could it just be in the capacitors of the PSU? I know on my old PSU the mobo lights could stay on for hours after unplugging it. To drain all the power in it, after flicking the switch on the back, press your front power switch. Lights should flick full on and then everything should be totally off.
 
UPDATE:

I have just shutdown the PC, switched off the PSU from the back.

Unplugged 2 fans from fan controller, the light obviously now goes off. I've plugged the fans directly into the motherboard and the fan light comes back on. This completely eliminates the fan controller. The motherboard is obviously getting some power coming from the PSU even thought the PSU is switched off.
 
Did you try what I said above? LED's on so many chargers and power packs etc stay on after they are unplugged due to residual power

Edit: I even managed to unplug a PC from one power strip and put it in another, while it was playing a game, without it turning off. Felt well pro :D
 
Ch3m1c4L said:
Did you try what I said above? LED's on so many chargers and power packs etc stay on after they are unplugged due to residual power

Edit: I even managed to unplug a PC from one power strip and put it in another, while it was playing a game, without it turning off. Felt well pro :D
Click to expand...

Maybe on a laptop with a battery but not a desktop.
 
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