4 signs that your CPU is overheating

A CPU shouldn’t run too hot unless you’re stress-testing it, but if it’s overheating under medium to heavy workloads, it’s probably time to replace the thermal paste or buy a better cooler. CPU overheating is pretty easy to notice if you use PC monitoring tools, but most people don’t always have them running 24/7. Sure, they come in handy when you’re testing the performance of a new game or rendering software you installed, but what about the rest of the time?

I’ve been using PCs for long enough that I now know if my CPU is running too hot without even opening monitoring software like MSI Afterburner. And that’s because I look out for some glaring signs that I’ve experienced over the past decade of owning gaming PCs and laptops.

4

Very loud fans

Your CPU fans almost sound like a jet engine

When your CPU runs hot during heavy workloads, the fans ramp up to bring its temperature down. Whether you use a desktop or a laptop, you’ll be able to hear them clearly as long as you don’t have your headset on. But if your CPU fans are too loud to the point that they’re annoying you, they’re probably running at 100% speed, which is a sign that your processor is running very hot and the fans are doing everything they can to lower the temperature.

Sometimes, the loud fans may also be a sign of a graphics card that’s running hot, especially if you encounter it while gaming. So, don’t be quick to jump to conclusions. If you’re using a laptop, an overheating GPU can also ramp up the CPU fans to reduce the chassis temperature. That’s why it’s important to monitor your PC using a tool like MSI Afterburner when this occurs to determine whether the CPU or the GPU is the culprit.

3

Hot chassis

Even your laptop’s keyboard is hot to the touch

An overheating CPU generates a lot of heat. If you’re using a laptop, you should be able to feel it easily; the keyboard will be uncomfortably warm to the touch because the CPU sits right below it. Alternatively, you can touch the bottom of the chassis or the air vents to see if it’s too hot. If you use a desktop, you can touch the side of the case right next to your processor or feel the hot air being exhausted through the radiator — in case you use a liquid cooler.

Laptop users can try using a cooling pad to alleviate the issue. But if that doesn’t help, you’ll have to open up the chassis, clean the internals, and replace the thermal paste to bring the temperature down. Desktop users can try cleaning the radiator fins and applying a new paste, but your only other option is to purchase a more powerful CPU cooler. If you have a high-end CPU like the Ryzen 9800X3D, I highly recommend getting a 360mm AIO liquid cooler like the Asus ROG Strix LC III 360 we reviewed.

Asus ROG Strix LC III 360 ARGB

The Asus ROG Strix LC III 360 ARGB can comfortably cool even the most powerful consumer CPUs like the AMD Ryzen 9800X3D and Intel Core Ultra 9 285K.

2

Random reboots and BSODs

Your PC just crashes due to instability

If your PC randomly shuts down when you’re in the middle of a demanding task — whether that’s gaming, streaming, or rendering — there’s a chance your CPU is overheating. Modern systems have safety measures in place to prevent CPU damage due to overheating. For instance, CPUs have a maximum temperature threshold known as TjMax (Thermal Junction Maximum), and when your CPU’s temperature exceeds this threshold, the PC shuts down to prevent hardware damage and allows the processor to cool down.

Oftentimes, the PC reboots automatically, but there are also instances where you encounter a BSOD (Blue Screen of Death). You typically encounter this error when there’s system instability. A CPU that’s running too hot doesn’t have the stability to perform its operations correctly, which leads to hardware errors that trigger a BSOD.

1

Sluggish performance

Your PC feels slow when running demanding tasks

When a CPU runs too hot, it won’t be able to deliver its maximum performance because of thermal throttling — a safety feature that lowers the CPU’s clock speeds to bring its temperature down. You’ll notice the effects of thermal throttling when you’re playing a game or running demanding applications. For example, the frame rate would suddenly drop while you’re gaming, or the cursor would start feeling sluggish. Sometimes, the app might crash or freeze altogether, forcing you to reboot your system.

An overheating GPU can also cause these issues, especially when gaming. However, if you’re experiencing slowdowns or lag even when your PC isn’t handling graphics-intensive tasks, your CPU is most certainly the culprit. This doesn’t mean your CPU is faulty, though. It’s just doing what it’s designed to do, i.e., lowering the CPU frequency to decrease the temperature. All you may need to do is replace the cooler or the thermal paste, but remember that there are other things that can cause thermal throttling, too.

Monitoring your CPU temperature is key

Once you notice that your CPU is indeed overheating, it’s time to note the temperature readings using your preferred monitoring software. When idle, your CPU should sit somewhere between 30 and 45C. When you’re gaming, it shouldn’t exceed 85C; otherwise, you’ll experience thermal throttling. However, when you’re stress-testing your CPU, you shouldn’t be surprised to see your CPU hitting 90C and above after a few minutes.

Remember that a powerful CPU needs a powerful cooler. A standard air cooler isn’t going to cut it for a CPU with a TDP of over 120 watts. Also, avoid using the stock thermal paste that’s included with your cooler if possible. Due to its high thermal conductivity, a high-performance thermal paste like Thermal Grizzly Kryonaut is much better at transferring heat from your CPU to the heatsink.

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