Can PSU Affect CPU Temp

Can PSU Affect CPU Temp? (5 Things You Should Know)

If your CPU’s temperature increases and you suspect that your old power supply is the culprit, then this article is for you.

I did a ton of research about the PSU’s impact on CPU temperature, and in this article, I will clarify all the concepts regarding this topic.

Here’s Can A Bad PSU Increase CPU Temp?

PSU’s wattage shouldn’t affect the CPU temperature, but the voltage does. 

A Bad power supply can cause high CPU temperature. If anyone severely stresses the PSU, it may give too high/ low voltage, which would cause the voltage regulation circuits on the motherboard and graphics card to work harder and generate more heat. Which rapidly increases the CPU temperature. But if you have an excellent cooling solution, then you can also prevent this issue.

Besides the cooling, the quality of the PSU also matters; the more influential the PSU is, the less heat it will produce as a byproduct of the power.

There are other reasons too which can cause the high CPU temperature issues, and all of these reasons are explained below.

CPU Temp is Too High: Is It PSU?

According to experts, the acceptable CPU temp ranges between 150 to 160 degrees Fahrenheit (65 to 70 degrees Celsius). Now, if your CPU temp is increasing over this benchmark, it can harm your systems.

A PSU can increase the CPU temp, but it’s an indirect cause; there are other direct reasons too, which can cause high CPU temp issues.

So, let’s look at how a PSU increase the CPU temp-

When power from the PSU goes to the PC components (such as GPU or Motherboard) in a more unstable manner, then the VRMs (Voltage Regulator Modules) components have to work harder to filter out the voltage fluctuations, which results in more heat output to both the GPU and the CPU depending on the filter results of the VRM circuitry.

The CPU temp sometimes increases in this process due to the slightly higher filtered voltage output. 

Now, we will explore some of the direct or primary causes which can also increase the CPU temp-

Bad CPU Fan

The CPU fan is one of the most integral parts of the computer system because it helps dissipate the system’s heat.

If your CPU fan gets damaged, it will cause different PC problems, including high CPU temperature issues.

So, whenever you face heating or high CPU temp issues, you initially need to inspect your CPU fan to determine whether it becomes faulty or not.

If the fan is faulty, then you need to replace the thermal paste; you can do it yourself by reading- replacing the CPU cooler guide. 

Bad Ventilation

Improper ventilation can also increase your CPU temperature. Your PC has the vents at the back of the PC case to ensure sufficient airflow.

You have to ensure that nothing is blocking this ventilation, and you can only know this by inspecting everything inside and outside the PC case.


As Wikipedia explains, overclocking is the practice of increasing the clock rate of a computer to exceed that certified by the manufacturer.

In simple terms, overclocking allows you to run your CPU at a higher clock speed than it was initially intended.

Overclocking often could cause overheating and temperature-related issues, especially if your computer and CPU weren’t built for high CPU usage and overclocking-related tasks.

Expired Thermal Paste

Thermal paste is a thermally conductive chemical compound commonly used to interface heat sinks and heat sources.

The Thermal Paste allows for an efficient transfer of heat from the processor’s heat sink to the cooler’s base plate.

If you don’t use the thermal paste between the CPU and heatsink, then it can cause overheating issues. Sometimes using expired thermal paste can also increase the temperature of the components. That’s why replacing your thermal paste time by time is always recommended.

So, if you notice that your CPU temperature is increasing, then these are the primary causes that need to be fixed. If everything is proper, then you can suspect your PSU.

Does PSU Wattage Affect The CPU Temp?

No! The PSU wattage has nothing to do with the CPU temperature. But if your PSU is old and pushing out unstable voltage, it can affect CPU temperature to some extent.

But, if you notice that your CPU temp is increasing significantly, then it’s not the PSU that is causing this issue; it’s something else.

You need to inspect all the other factors like a CPU fan, thermal paste, ventilation and whether you are doing overclocking or not.

Does A PSU Upgrade Improves CPU Temperature?

Hypothetically upgrading PSU cause a minimal improvement in CPU temperature but not by any significant amount. 

If your current power supply is exhausting hot air into the case, as swapping to a more efficient PSU would result in less heat. Moreover, having cleaner power delivery to your VRM would reduce the amount of heat generated by the input filtering capacitors, but otherwise, it doesn’t bring any improvement.

CPU is Running Hotter After Boughting A New PSU

Many people complain that after upgrading the old PSU to a new one, their CPU is running hotter than initially.

Yes! Sometimes after upgrading to a new PSU, your CPU run hotter, especially if your current PSU is at its limits. As a higher capacity model, it would provide a more incredible amount of power to the CPU and GPU more consistently, which would result in a more significant amount of power dissipating as heat and, therefore, higher temperature.

Final Thoughts

Based on all the factors, it’s clear that only the PSU doesn’t cause high CPU temp-related issues; if you are facing this kind of issue, then you have to check some other factors like- CPU fan, ventilation, thermal paste etc.

I hope this article clears all of your doubts and if you want to know more about the PSUs, CPUs and other PC components, then follow this blog regularly.