Question New build boots fine from motherboard 'start' but gets CPU FAN ERROR when turned on from case's power button

[Thulie313]

I need major help please, I've looked everywhere but can't find anyone with this issue

I've recently built a new pc, mostly using parts from my old build

I used these parts:
- Intel Core i7-4790K
- Lian Li Galahad II Trinity SL-INF 61.3 CFM Liquid CPU Cooler (new part)
- Asus MAXIMUS VII RANGER ATX LGA1150 Motherboard
- Asus ROG STRIX-GTX1070
- Lian Li O11 Air Mini ATX Mid Tower Case (new part)
- EVGA 850 GQ 850 W power supply

Here is my issue, when I press the power button on the case, I get CPU fan error message, then F1 to go to BIOS. In BIOS, my CPU temp is rising every 1 second. within 10 seconds it goes from 30° to 70° and it keep rising so I shut it down before it goes in the 80s.

However when I power my computer from the 'start' button on the motherboard, the computer starts perfectly fine, no CPU fan error. This is how I managed to install windows 11 and update it, also used the computer for a few hours without issues. I checked CPU temps via hwmonitor and everything runs smoothly.

But then when I boot it from the power button on the case, same problem all over again, CPU fan error, temps rising in BIOS. Does anyone know why? Because I really don't want to leave the case open and just boot from the motherboard every time.

 

[KingLoki]

So if you boot from the case power button, no cpu fan spins at all?

 

[Thulie313]

So if you boot from the case power button, no cpu fan spins at all?

Actually the CPU fan spins when I switch it on from the case. All the fans in the case spin as normal regardless how I switch it on. All the RGB lights also work.

The only issue occurs when using the case power button, the 'CPU fan error' message appears which forces me to go to BIOS, and the rapidly rising CPU temperature in BIOS. If I leave it to reach the 78 degrees then I can hear one of the fans getting louder at which point I switch it off.

Also if the computer is already turned on, restarting it does not cause any problems. It will restart as normal.

 

[KingLoki]

Have you tried connecting the fan to both CPU_FAN and CPU_OPT headers?
I think you may have the wired fan connector on the wrong header... ? It should be on the CPU_FAN header otherwise it can cause a bios error.
Each fan header has its own related speed settings for the bios.

 

[Thulie313]

Have you tried connecting the fan to both CPU_FAN and CPU_OPT headers?
I think you may have the wired fan connector on the wrong header... ? It should be on the CPU_FAN header otherwise it can cause a bios error.

Yes, there was no difference in using either.

Currently the wire that comes out of the AIO pump is connected directly to CPU_FAN

But you might be right, I must have done something wrong. I still don't understand how it can still boot up and run for hours if there was an issue.

I thought it might be something wrong with the BIOS settings causing the AIO pump to not work

 

[KingLoki]

it's unusual to get an error when it's connected to CPU_FAN ??

It’s possible to bypass this message by simply running the BIOS setup and exiting. To permanently get rid of this issue, set the Minimum Fan Speed to Ignore. The particular option varies based on the motherboard.

 

[Thulie313]

Tomorrow I'll take everything out and rewire. Something might be loose.

Do you think the CMOS battery could be causing an issue? Maybe I should replace it

 

[KingLoki]

Have a read of this regarding All-inOne coolers

Where do you Connect Your AIO Pump on your Motherboard?

Modern Motherboards have specific Fan headers for AIO Coolers. Here's an overview guide of where to connect your All-In-One CPU Water Cooler.

www.cgdirector.com

 

[KingLoki]

You can replace if it's years old.

 

[Thulie313]

Have you tried connecting the fan to both CPU_FAN and CPU_OPT headers?
I think you may have the wired fan connector on the wrong header... ? It should be on the CPU_FAN header otherwise it can cause a bios error.
Each fan header has its own related speed settings for the bios.

Hey, I think I fixed it.

So your reply here got me thinking a little so I looked around a and found this

https://www.reddit.com/r/lianli/s/n5qEWbLSlk

Obviously the motherboard wasn't detecting the CPU fan during certain boot ups (although a boot up directly from the motherboard had no issues)

So I connected the pump to CPU_OPT (instead of CPU_FAN)

Then as not to get an error, I connected the rear fan to CPU_FAN. Just so that something is there to be detected.

I then booted it from the power button on the case and there was no error or issues. Temperatures are all good too.

It's a bit late here so I'll test it again in the morning but I think that did the trick.

Seems like poor design from Lian Li...

 

[KingLoki]