CPU Over Temperature Error – Causes and Solutions 2025!

A CPU Over Temperature Error means your processor is overheating. It usually appears during startup or heavy use when cooling fails. Check the fan, clean dust, and ensure proper airflow to prevent slow performance, crashes, or CPU damage. Fixing it early keeps your system safe and stable.

If your PC suddenly shuts down or sounds like a jet, this guide will help you fix it fast.

What is CPU Over Temperature Error?

A CPU Over Temperature Error is a safety warning that appears when your processor crosses its safe heat limit. The system stops or restarts to protect the CPU from burning out. It usually shows up on boot or under heavy tasks when cooling is not working properly, such as blocked fans, bad airflow, or dry thermal paste.

Why Does My PC Keep Showing CPU Over Temperature Error?

Your CPU overheats when it generates more heat than your cooling system can remove. This happens if the airflow is poor, thermal paste has dried, or the fan is not working properly. When heat builds up too fast, the system triggers a CPU Over Temperature Error.

Main causes include:

• Dust buildup is blocking airflow in the case or the CPU fan.
  
• Thermal paste dried out or was applied unevenly.
  
• CPU cooler is not seated properly on the chip.
  
• A non-spinning or disconnected fan triggers a CPU error.
  
• Overclocking without enough cooling power.
  
• Cable clutter stops air from moving freely.
  
• High ambient temperature raises system heat.

Also Read: Is 80 Degrees Celsius Hot for a CPU? – Safe Temp 2025!

How to Confirm If CPU Is Actually Overheating?

To confirm if your CPU is really overheating, check its real-time temperature using trusted tools. This helps you see if the BIOS error is true or just a sensor glitch.

Ways to confirm overheating:

• Enter BIOS setup and check the CPU temperature reading, this is the best way to confirm overheating if your BIOS temperature warning keeps showing.
  
• Use tools like HWMonitor, Core Temp, or MSI Afterburner.
  
• Look for sudden system lag, shutdowns, or freezes.
  
• Touch the PC case near the CPU if it is unusually hot, there is an issue.
  
• Watch the fan speed if it’s not spinning, cooling has failed.
  

CPU Temperature Range	Status	Meaning / Action
30°C – 50°C	Normal	Ideal idle or light use temperature
50°C – 70°C	Moderate	Normal under gaming or load
70°C – 85°C	High	Check cooling and airflow
85°C – 95°C	Overheating	Risk of shutdown or error
95°C+	Critical	Immediate danger, shut down the system

How Do I Fix CPU Over Temperature Error When My PC Starts?

A CPU overheating issue on startup means the processor is getting too hot even before Windows loads. This usually happens due to dust buildup, loose cooling, or old thermal paste. To fix it quickly, clean the cooling system, reseat the CPU cooler, and check BIOS fan settings.

Detailed Steps:

1. Shut down your PC and let it cool down for a few minutes.
   
2. Open the case and clean dust from all fans, vents, and heatsinks.
   
3. Make sure the CPU cooler is mounted tightly and evenly.
   
4. Reapply a thin layer of fresh thermal paste if the old one looks dry.
   
5. Power on your system and ensure all fans spin properly; replace any faulty ones.
   
6. Enter the BIOS, then open Hardware Monitor and confirm the CPU temperature stays below 80 °C.
   
7. If the error continues, reset BIOS settings to the default.

Also Read: CPU Fan Error on Boot – Fix It Now 2025!

Why BIOS Shows CPU Over Temperature Error?

BIOS shows a CPU Over Temperature Error when it detects that the processor’s temperature is higher than the safe limit, usually above 80–90°C. This warning protects your system from damage caused by overheating. The main reasons include poor airflow, dust buildup, failing fans, or a loose CPU cooler.

CPU Fan Error vs CPU Over Temperature Error:

A fan error means the cooling fan isn’t working or being detected, while an overheating warning means the processor is getting too hot. Both issues are linked if the fan stops, heat builds up quickly. Always fix fan problems first to prevent temperature errors or system shutdowns.

• The fan cable is connected to the wrong header, like CHA_FAN instead of CPU_FAN.
  
• The fan has failed or stopped spinning due to dust buildup.
  
• BIOS settings have incorrect fan speed thresholds.

In short:

Error Type	Main Cause	Quick Fix
CPU Over Temperature Error	CPU gets too hot (above safe limit)	Improve cooling, clean fans, reapply thermal paste
CPU Fan Error	Fan not working or not detected	Reconnect or replace the fan, check BIOS settings

Pro Tip: A CPU Fan Error can lead to an Over Temperature Error if ignored, so always fix the fan issue first.

How to Fix CPU Over Temperature Error on ASUS Motherboard?

Make sure your cooler is fitted properly and fans are clean for better airflow. Reapply thermal paste and reset BIOS settings if overheating continues.

Follow these steps to fix overheating safely:

• Check CPU cooler installation: Make sure it is tightly fitted and not loose.
  
• Clean dust from fans and heatsinks: Dust blocks airflow and increases heat.
  
• Reapply thermal paste: Use a small amount of high-quality paste between the CPU and cooler.
  
• Enter BIOS and reset settings: Press Del or F2, go to Exit, and select Load Optimized Defaults.
  
• Update BIOS: Visit ASUS’s support site and flash the latest BIOS for better temperature control.
  
• Monitor fan speed: Ensure CPU_FAN and CHA_FAN headers show proper RPM.

These fixes help clear the error and keep your ASUS system running cool and stable.

If CPU Fan Stops and Triggers Over Temperature Error?

If the CPU fan stops, the processor can heat up quickly. Shut down your PC, check that the fan cable is connected properly, and clean any dust. If the fan still does not spin, replace it or verify in BIOS that the fan is detected. This prevents overheating and system shutdowns.

Cooling & Prevention Tips After Overheating:

To cool down your CPU, shut down your PC and clean the dust from the fans and vents. Reapply thermal paste if old and ensure proper airflow inside the case. Regular cleaning, good ventilation, and avoiding overclocking help prevent future overheating errors.

• Keep your PC clean and free of dust every month.
  
• Replace thermal paste once a year.
  
• Maintain good case airflow with proper fan placement.
  
• Avoid overclocking without advanced cooling.
  
• Monitor CPU temps regularly using trusted tools.

How to Monitor CPU Temp and Fan Speed Safely?

Monitoring CPU temperature and fan speed helps you catch heat problems early. You can use built-in tools or third-party apps for accurate results. Regular monitoring ensures your CPU stays within safe limits and prevents sudden shutdowns.

• Open BIOS or UEFI to view real-time CPU temperature and fan RPM.
  
• Use software like HWMonitor, Core Temp, or HWiNFO for detailed readings.
  
• Keep background apps closed while testing for accurate data.
  
• Note any sudden fan speed drops or unusual heat spikes.

You may also like: How to Check CPU Power Consumption? – Complete Guide 2025!

Best Tools to Check CPU Heat and Sensors?

You can easily track CPU heat and sensor data using reliable monitoring tools. These help you detect issues before they become serious.

• HWMonitor: Shows CPU temperature, voltage, and fan speed in real time.
  
• Core Temp: A Lightweight app for quick temperature checks.
  
• HWiNFO: Advanced tool for deep system analytics.
  
• NZXT CAM: User-friendly interface with gaming overlays.
  
• Open Hardware Monitor: Free and open-source option for all sensors.

FAQ’s:

Conclusion:

Fixing the CPU Over Temperature Error is easy if you maintain your cooling system and keep your PC clean. Regularly monitor CPU temps, check fan speed, and reapply thermal paste when needed. These small steps prevent overheating, reduce CPU heat, and keep your processor running efficiently for years.