[SOLVED] AIO fans not spinning after bios update ?

[inoku]

I have a B550m-a Pro Motherboard, I upgraded from 3500x to a 5900x (updated to the newest BIOS as well) I noticed that my AIO fans are not spinning even though before the upgrade they did on the 3500x and old bios. I've checked all the cables and everything seems as it was as I did not play with them. In Bios I see 2500rpms even though it's not the AIO fans, I'm guessing it's the pump RPMS ? The RGB works on the fans yet they're not spinning, I've put every fan to the max and still nothing, idk what to do.

 

[1LiquidPC]

Are the fans being shown/detected at all in the BIOS? 2500 likely is the pump RPM as that's normal for AIOs. Fan speeds are usually much lower RPM by default. Which fans are connected to which header and where is pump connected in your case? What AIO are you using?

 

[inoku]

Are the fans being shown/detected at all in the BIOS? 2500 likely is the pump RPM as that's normal for AIOs. Fan speeds are usually much lower RPM by default. Which fans are connected to which header and where is pump connected in your case? What AIO are you using?

I'm using a Coolermaster 240 lite with RGB cooler master fans, and yeah it's at 2500 rpms, so my pump is connected to CPU fan, it's a 3 pin into 4.
All of my other fans are working except the AIO one, just the RGB on them works.

There's a 4 pin connected to sys fan. And that's about all the motherboard has for the fans, only two connectors as I'm noticing on the motherboard. I bought it custom prebuilt.

 

[Paperdoc]

On a mobo the CPU_FAN header ALWAYS uses the temperature sensor inside the CPU chip to guide its cooling fan. The SYS_FAN headers on the mobo use a different sensor on the MOBO, not the one inside the CPU chip. The way your AIO system is connected makes some sense only IF the SYS_FAN header that is used for the rad fans is changed to use the CPU internal temp sensor, which come mobos allow.

Now, because of the CPU upgrade, you updated the BIOS as you should. But that also means that the new BIOS you have is set by default to use the mobo temp sensor for the two SYS_FAN headers. They also may well be set to run those fans so slow at cool start-up conditions that they stall. You will need to change the settings for the SYS_FAN header that feeds the rad fans.

Tell us you mobo maker and exact model so we can give you specific advice.

 

[inoku]

On a mobo the CPU_FAN header ALWAYS uses the temperature sensor inside the CPU chip to guide its cooling fan. The SYS_FAN headers on the mobo use a different sensor on the MOBO, not the one inside the CPU chip. The way your AIO system is connected makes some sense only IF the SYS_FAN header that is used for the rad fans is changed to use the CPU internal temp sensor, which come mobos allow.

Now, because of the CPU upgrade, you updated the BIOS as you should. But that also means that the new BIOS you have is set by default to use the mobo temp sensor for the two SYS_FAN headers. They also may well be set to run those fans so slow at cool start-up conditions that they stall. You will need to change the settings for the SYS_FAN header that feeds the rad fans.

Tell us you mobo maker and exact model so we can give you specific advice.

MSI B550M-A Pro

 

[Paperdoc]

I am surprised to see the mobo specs say there are only two fan headers- CPU_FAN and SYS_FAN. You say the PUMP is plugged into CPU_FAN, and the RAD FANS are plugged into the only SYS_FAN header (presumably using a Splitter). So do you have NO CASE Ventilation fans at all, other than the air brought in by the rad fans? Are you sure the RAD FANS are plugged into the only SYS_FAN header?

Anyway, the Manual I could find shows virtually no info on fan header configuration options. So this will be what is common, but may not match yours exactly. Go into BIOS Setup and find the configuration screen for the SYS_FAN header. Set its PROFILE to "Normal" or "Standard". Check carefully the choices for MODE. They will be PWM Mode, Voltage Mode (aka DC Mode), and possibly Auto. Set to PWM Mode. Now look for the choice of temperature sensor. Set that to CPU, not MOBO.

While there, go next to the CPU_FAN header. Make sure it is set to PWM Mode also, so that the pump will get a constant full 12 VDC and run full speed all the time as designed.

When you've made your setting changes, use Esc back to the Main Menu, then F10 to get to the Exit Menu. There choose to SAVE and EXIT to save your settings and reboot. ALL the fans should start at full sped briefly, and then slow down for a cool system, but NOT stop EVER until you shut down. If things do not go that way, post back here what you do see.

 

[inoku]

I am surprised to see the mobo specs say there are only two fan headers- CPU_FAN and SYS_FAN. You say the PUMP is plugged into CPU_FAN, and the RAD FANS are plugged into the only SYS_FAN header (presumably using a Splitter). So do you have NO CASE Ventilation fans at all, other than the air brought in by the rad fans? Are you sure the RAD FANS are plugged into the only SYS_FAN header?

Anyway, the Manual I could find shows virtually no info on fan header configuration options. So this will be what is common, but may not match yours exactly. Go into BIOS Setup and find the configuration screen for the SYS_FAN header. Set its PROFILE to "Normal" or "Standard". Check carefully the choices for MODE. They will be PWM Mode, Voltage Mode (aka DC Mode), and possibly Auto. Set to PWM Mode. Now look for the choice of temperature sensor. Set that to CPU, not MOBO.

While there, go next to the CPU_FAN header. Make sure it is set to PWM Mode also, so that the pump will get a constant full 12 VDC and run full speed all the time as designed.

When you've made your setting changes, use Esc back to the Main Menu, then F10 to get to the Exit Menu. There choose to SAVE and EXIT to save your settings and reboot. ALL the fans should start at full sped briefly, and then slow down for a cool system, but NOT stop EVER until you shut down. If things do not go that way, post back here what you do see.

I have 2 fans at the front and 1 at the back. Those work except the AIO fans.

Bios only detects pwm on both, sys fan and cpu fan. Can't change it either to any other mode.

For CPU fan it's giving me the rpms of the pump I'm guessing, and sys fans of course I can turn them up and down, I switched the headers even between them both to see if anything changes and still nothing.

I can't figure it out, so I gave the pc to a specialist see if he can get it to work. If not I'm just going to buy a new cooler and assume the fans are dead on the AIO or something with the splitter/controller (I have not checked the splitter/controller at the back of the case). Will find out once the specialist finds out the problem, he has 28 years of experience in the field.

So I have a 750w PSU gold rated Corsair, I'm assuming it would be enough power for a 3070 Suprim X and 5900x. I hope the CPU has nothing to do with the fans not spinning either on the AIO.
Or it's something with the motherboard, could be many things. Idk. Will see.

 

[Paperdoc]

As background: the speed of a fan is a signal sent from the fan back to its mobo header via Pin #3. You can "see" a fan's speed only from the header it is plugged into. In OP's case, what i plugged in at CPU_FAN is the PUMP, so yes, that is the pump speed displayed there.

OP, you say, "I have 2 fans at the front and 1 at the back. Those work except the AIO fans." Do you mean that there are three fans in your case IN ADDITION to the Rad Fans, or are the Rad fans part of that 3-count? Adn WHERE are all of these plugged in? There has to be some other component to have more than one fan connected to the only mobo SYS_FAN header.

 

[inoku]

The aio controller was dead therefore the fans on the aio did not spin as probably the fans died with it too.

Bought a new aio: m240l v2, not the biggest of an upgrade however it does the job regardless. Hopefully the controller doesn't die on this one.

 

[Paperdoc]

Thanks for the update.