Power Supply fan running at full speed (new build)

[mrkhly89]

Hi.

I just put together my new PC and now the PSU fan runs at full speed.

This did not happen on the first few boot-ups. Everything was normal, I installed windows 10 and was half way through updating when the fan spinned up to max and now it constantly runs at max.

Yes I am sure that it's the PSU fan and that it's not a heat problem, the PSU is blowing out cold air.

All new parts: Seasonic Prime Platinum 750W, MSI gaming M5 motherboard, i7 7700k, MSI gtx1080Ti.

There is no fan control wire to the PSU and its plugged directly into the wall.

The only thing I can think of is that I bought the PSU on Newegg, from the USA and it came with a US style 125V plug. Of course I am using a European 220V (kettle) lead. Don't know if this is a problem because the fan didn't spin up until after i had installed windows.

Any help is appreciated.

Mark

 

[SirSub42]

From what I understand, power supplies come with a variable speed fan, so they will spin as fast as they deem necessary.
https://www.bhphotovideo.com/c/product/1322729-REG/seasonic_electronics_prime_ssr_750pd_750w_platinum.html
Yours seems to be good to go.

 

[mrkhly89]

From what I understand, power supplies come with a variable speed fan, so they will spin as fast as they deem necessary.
https://www.bhphotovideo.com/c/product/1322729-REG/seasonic_electronics_prime_ssr_750pd_750w_platinum.html
Yours seems to be good to go.

The fan is running at max speed constantly. I'm pretty sure it's not meant to do that.

 

[DRagor]

On the back of the PSU, next to on/off switch, there is another switch. It is used to change PSU fan behavior. It is quite possible you accidentally push it, and now the fan behaves differently then it did before.
If it's not that, it could mean PSU is not working properly.

 

[mrkhly89]

On the back of the PSU, next to on/off switch, there is another switch. It is used to change PSU fan behavior. It is quite possible you accidentally push it, and now the fan behaves differently then it did before.
If it's not that, it could mean PSU is not working properly.

Thanks for the reply. That switch doesn't seem to have any effect. It just runs at full speed all the time. I opened a ticket with Seasonic. Something in my gut is telling me it's got something to do with the graphics card. It happened after installing the Nvidia updates.

 

[DRagor]

Thanks for the reply. That switch doesn't seem to have any effect. It just runs at full speed all the time. I opened a ticket with Seasonic. Something in my gut is telling me it's got something to do with the graphics card. It happened after installing the Nvidia updates.

If the switch does nothing, then it's surely failed PSU. When passive fan mode is enabled by this switch, the PSU fan should turn off at all and stay that way until PSU gets hot enough. My guess is temp sensor on PSU has died.

 

[mrkhly89]

Thanks for the reply. That switch doesn't seem to have any effect. It just runs at full speed all the time. I opened a ticket with Seasonic. Something in my gut is telling me it's got something to do with the graphics card. It happened after installing the Nvidia updates.

If the switch does nothing, then it's surely failed PSU. When passive fan mode is enabled by this switch, the PSU fan should turn off at all and stay that way until PSU gets hot enough. My guess is temp sensor on PSU has died.

Thank you, that makes sense. I'm going to try a different PSU on the rig anyway to see if the same thing happens.

 

[DRagor]

Thank you, that makes sense. I'm going to try a different PSU on the rig anyway to see if the same thing happens.

Do that if you can, just make sure the other PSU has enough power - your rig needs quite a lot of it.

 

[mrkhly89]

Do that if you can, just make sure the other PSU has enough power - your rig needs quite a lot of it.

I tried another PSU and it ran quietly with no problem. So it looks like a failure in the unit like you said. I will have to send it back.

 

[DRagor]

Do that if you can, just make sure the other PSU has enough power - your rig needs quite a lot of it.

I tried another PSU and it ran quietly with no problem. So it looks like a failure in the unit like you said. I will have to send it back.

Good, but make sure the problem will not come back again after few boots with the other unit. Not likely, but better to be sure before you send PSU only to find out it was not it.

 

[mrkhly89]

Good, but make sure the problem will not come back again after few boots with the other unit. Not likely, but better to be sure before you send PSU only to find out it was not it.

I'll do that, thank you.