How To Fix CPU Fan Speed Error Detected? [6 Methods]

If your CPU fan or cooler isn’t installed correctly on the motherboard, you may get a message that reads ‘CPU fan speed error detected,’ and you won’t be able to boot into your PC. These errors can be fixed by tweaking some settings in BIOS and a few other methods.  

Key Takeaways 

• CPU fan speed error detected message means that your CPU isn’t receiving enough cooling and prevents you from booting into Windows. 
• The error occurs when your CPU fan isn’t working correctly, it’s not connected properly, or the motherboard can’t detect it.  
• To fix this error, you can install the CPU fan and AIO cooler properly, adjust the CPU fan RPM, fix CPU overheating, and tweak the BIOS settings. 

What Causes CPU Fan Speed Error?

The CPU fan speed error message appears when your motherboard detects an improperly installed CPU fan or cooler. This can cause your CPU to function without proper cooling and get damaged.  

Also Read: How To Fix AIO CPU Fan Not Working

The motherboard prevents you from booting into your computer by displaying this error message. However, the error can occur even if your CPU fan or cooler is correctly installed on the motherboard.   

For ASUS motherboards, you will see the error message ‘CPU fan speed error detected.’ The error may be written simply as ‘CPU fan error detected’ and other variations on different motherboards. 

While there is a way to bypass this error by tweaking some settings in BIOS, I’ll advise you not to do that, as the error means your CPU isn’t receiving proper cooling. Ignoring this error can cause damage to your CPU as well as other components on your PC.  

How To Fix CPU Fan Speed Error? 

Now that you know why the CPU fan speed error is occurring on your PC, I’ll guide you through the different methods you can use to fix this issue.  

Properly Installing The CPU Fan

The most common reason for the ‘CPU fan speed error detected’ message to appear on your PC is that the CPU fan isn’t connected to the CPU_FAN header on the motherboard.  

You may have plugged the CPU fan into another fan header on your motherboard, like the SYS_FAN error or CHA_FAN header. If this is the case, the motherboard will display the error message.

To fix this problem, you should ensure that the CPU fan header is correctly installed on the CPU_FAN header on the motherboard. You can locate the CPU_FAN header by using the motherboard’s manual and by checking the text beside the header. Also, ensure that the backplate, screws, thermal paste, and other components of your CPU cooler have no problems.  

Also Read: How To Remove Intel CPU Fan/Cooler?

Correctly Installing The AIO Pump

Installing an AIO cooler for the first time can be a bit confusing, and you may have mixed up the headers on your motherboard, which can be why you’re getting the CPU fan speed error.

Firstly, check if your AIO pump is connected to the proper AIO_PUMP header on your motherboard. Then ensure that a fan is connected to the CPU_FAN header. You will get the error if the CPU_FAN header is left vacant but the AIO_PUMP header is connected.

So you can fix this issue by connecting the components of your AIO cooler to their correct headers on the motherboard. Also, ensure that your AIO’s other parts are correctly installed. 

Also Check: Answered: How Long Does An AIO Liquid Cooler Last?

Adjusting CPU Fan RPM 

You may find it even when your CPU fan and cooler are correctly installed in your motherboard; you may still get the error. One of the main reasons for the ‘CPU fan speed error detected’ message appearing on your PC is the slow-spinning CPU fan. 

If you have a CPU fan that automatically reduces its RPM or stops when the CPU temperature is low, then your motherboard may not be able to detect it and will display the error message. 

Also Read: CPU Clock Speed

You must change the CPU fan RPM settings from your computer’s BIOS to fix this. To do that, follow these steps:

1. Press the F1 key when the error is displayed to enter the BIOS. 
2. Go to Advanced Mode and navigate to the Monitor tab.  
3. From the ‘CPU Fan Speed Low Limit‘ option, set the fan speed to 200 RPM.

   

4. Press the F10 key and select Ok to save your changes, and exit the BIOS.

Updating BIOS

Some ASUS motherboards get the CPU fan speed error detected message when the BIOS isn’t updated correctly. You need to install the newest BIOS version on your PC to eliminate this error. 

First, you need to check which BIOS version is currently installed on your PC. To do that, follow these steps: 

1. Open the BIOS settings by pressing the F1 key when the error is displayed. 
2. Select Advanced Mode and check your BIOS version under the Information tab.

You can update the BIOS using the EZ Update feature in the AI Suite software provided for the ASUS motherboards. 

Fix CPU Overheating Issues

If your CPU is overheating and your current CPU cooler isn’t helping maintain the temperature, you may get the CPU fan speed error detected message.  

To fix this, you should disable any overclocking settings you may have applied to your computer and reset the BIOS to default settings.  

You should also place your PC in a cool environment, clean the CPU fans thoroughly and blow the dust out of your PC. Having a good airflow solution is also a good idea so your CPU remains as cool as possible. We also have a guide on how to clean a PC without compressed air. 

Related Article: How To Lower CPU Temperature [15 Methods]

Changing BIOS Settings 

If none of the methods worked for you and you’re still getting this error on your PC, you should try changing your BIOS settings to bypass the error. To do that, follow these steps:  

1. Press the F1 key to access the BIOS setup when the error is displayed. 
2. Press the F7 key or click the Advanced Settings option on the bottom right.  
3. Select the Monitor tab and look for the CPU Fan Speed setting.   
4. Change it from N/A to Ignore.  
5. Press the F10 key and select Ok to save your changes. 

Now the computer will automatically restart, and you should be able to boot into Windows without any problems. But remember that doing this will only make the motherboard ignore the error instead of fixing it, but if your CPU temperatures are cool, everything should be fine.  

Also Read: How To Reset BIOS Settings 

Final Thoughts 

If you tried all the methods I mentioned in this guide and they didn’t work for you, it may be that your CPU fan or cooler is broken, in which case you may have to replace it with a new one. But before doing that, I would advise you to get your PC checked by a hardware technician. If you decide to get a new CPU cooler, check out our guide on how to buy a CPU cooler.