Quick Answer
There are a few potential reasons why your computer may be buzzing or making noise when it gets hot:
- The CPU fan is working harder to cool the CPU – As the CPU heats up, the fan speeds up to try to keep it cool. This can cause a buzzing or whirring noise as the fan spins faster.
- Coil whine from components – Some components like power delivery circuits can emit a high-pitched buzzing or whining noise when under load. This noise arises from vibrations in inductors and capacitors.
- Expanding/contracting components – Heat causes metal and plastic parts to expand slightly. This can cause them to rub or vibrate against each other, creating buzzing noises.
- Faulty or dusty fan – If a fan has bearings that are worn out or is clogged with dust, it can start to buzz or grind as it has difficulty spinning.
So in summary, the most likely culprit is the CPU fan working harder as the CPU heats up. But coil whine and vibration of components can also sometimes play a role in hot-related buzzing noises. Checking fans for blockages and replacing any that are worn out can help.
What causes the buzzing noise when a computer overheats?
There are a few main components in a computer that can cause buzzing noises when they get hot:
CPU Fan
The CPU (central processing unit) is one of the main heat-generating components in a computer. To keep the CPU cool, there is a fan mounted on top of it or adjacent to it that blows air over its surface.
As the CPU starts to heat up with increased processing load, the fan will automatically spin faster in an effort to keep the temperature down. This increase in fan speed causes more air turbulence and friction, which translates into a buzzing or whirring noise.
Many CPU fans these days use ball bearings that can start to wear out over time. A degraded bearing in the fan can also lead to a buzzing noise as the fan has difficulty spinning smoothly.
Graphics Card Fan
The graphics card is another heat-producing component. Graphics cards have their own fans, usually two or three small fans mounted on the card’s shroud. Much like the CPU fan, these fans will spin faster when the graphics card is hot in order to maintain good airflow.
Graphics card fans are generally smaller than CPU fans and have to spin very fast to move enough air. This can lead to a high-pitched buzzing noise coming from the graphics card area when gaming or running graphically intensive programs.
Power Supply Fan
Inside the power supply unit (PSU) there is a fan that blows air across internal components to keep them cool. As the PSU heats up under load, this fan also has to work harder. A worn-out or unbalanced power supply fan can produce buzzing noises in some cases.
Coil Whine
Coil whine refers to a high-pitched electronic squealing or buzzing noise that comes from the vibration of inductors and transformers on the motherboard or graphics card. It occurs when they’re rapidly switching DC power on and off.
The noise arises from the coils of wire and core materials physically vibrating. More load and current flow means more vibration, and thus more noise. It’s most common to hear coil whine from graphics cards, but motherboard voltage regulator modules can also sometimes emit it under load.
Rattling and Vibration
When components heat up, they also physically expand and move slightly, due to thermal expansion. This can cause normally tight-fitting parts like heatsinks to rub or vibrate against each other, creating a buzzing noise.
The high airflow from fans can also cause loose cables or components to vibrate against each other and buzz slightly. Basically, the increased vibration and component movement caused by heat can translate into audible buzzing noises in some cases.
How can I fix the buzzing noise?
Here are some troubleshooting tips to stop your computer from buzzing when overheating:
Clean Out Dust Buildup
Open up the case and use compressed air to blow out any dust buildup on fans and heatsinks. Dust clogs up fans and heatsinks, reducing their cooling capacity. This forces the fans to work harder, causing buzzing.
Check CPU Fan
Unplug the CPU fan and give it a spin with your finger. Does it make a smooth whirring sound? Or does it grind/buzz? If it’s buzzing, the fan’s bearing is likely worn out and the fan needs replacement.
Replace Faulty Fans
If cleaning doesn’t fix buzzing fans, they may just be worn out. Many case and CPU fans use sleeve or rifle bearings that can wear out over a few years. Replace any fans that are making excessive noise due to degraded bearings.
Update BIOS
For coil whine, check your motherboard manufacturer’s website for a BIOS update. Updated BIOS code can sometimes reduce coil whine from the voltage regulator modules.
Use Sound Dampening
Stick small pieces of rubber or silicone isolators on vibrating components to dampen buzzing from contact. Larger silicone grommets can be used to suspend and isolate hard drives that are buzzing in their bays.
Limit FPS
If your graphics card is buzzing from coil whine, limiting the frame rate to your monitor’s refresh rate can help by reducing the workload on the GPU. Use a frame rate limiter utility or enable Vsync.
Add Capacitors
Soldering small ceramic capacitors onto the coils and phases making the noise can sometimes limit coil whine. This helps filter the power delivery and reduces vibration. But this mod requires soldering skills.
How can I prevent my computer from overheating and buzzing?
Here are some tips to keep your computer running cool and prevent overheating and noise:
Clean the Computer
Regularly clean out dust buildup from your computer, especially on fans and heatsinks. Compressed air works well for blowing out dust. This allows for proper airflow and cooling.
Replace Thermal Paste
Every few years, replace the thermal paste between the CPU and heatsink. Old dried up paste reduces heat transfer efficiency, causing the CPU to run hotter.
Improve Airflow
Make sure your computer case has adequate intake and exhaust airflow. Add extra case fans if needed. Position fans to create a smooth front-to-back airflow path across components.
Use an Aftermarket CPU Cooler
Upgrade to a better CPU cooler like a tower air cooler or all-in-one liquid cooler. Aftermarket coolers outperform the basic heatsinks that come with CPUs. This keeps the CPU cooler.
Don’t Overclock
Avoid overclocking your CPU/GPU which increases heat output and power draw. Stick to stock speeds if heat is already an issue.
Check Location
Make sure your computer case has enough clearance on all air vents and isn’t jammed in an enclosed space. Place it somewhere air can easily flow around it.
Case Airflow Mods
Consider adding ventilation holes, mesh panels, or swapping in bigger fans to improve case airflow. Just take care not to compromise case structure or aesthetics.
Undervolt Components
Undervolting the CPU and GPU can slightly reduce power consumption and heat output while maintaining full performance. Just be cautious and stress test for stability.
Conclusion
In summary, the main culprit for computer buzzing noises when overheating is usually the CPU fan spinning faster to try to dissipate heat. Other common causes include faulty power supply fans, graphics card coil whine, and rattling from components rubbing together.
To fix the issue, thoroughly clean your computer of dust buildup, replace any worn-out fans, check for BIOS updates, limit framerates, isolate buzzing components with rubber/silicone, and consider adding capacitors for coil whine.
Preventative measures include keeping your computer clean, using quality thermal paste, installing extra airflow fans, upgrading the CPU cooler, avoiding overclocking, carefully positioning the case, and undervolting if possible. With vigilance and proper maintenance, you can keep your system running cool and quiet.
| Cause of Buzzing | Description | Fixes |
|---|---|---|
| CPU Fan | Spins faster when CPU is hot, causing buzzing noise | Clean fan, replace if worn out |
| Graphics Card Fan | Small fans on GPU spin fast and can buzz | Clean fan, check for rattle, replace if worn |
| Power Supply Fan | Overheated PSU fan buzzes when working hard | Clean fan, replace PSU if fan faulty |
| Coil Whine | Electronic buzzing from vibrating coils in GPU or motherboard | BIOS update, limit FPS, add capacitors |
| Rattling | Heat makes components vibrate and rattle against each other | Isolate with rubber/silicone dampeners |
