Tell If A CPU Is Dead, look for these signs: no response when powering on, no display output, or unusual beeping sounds. Consult a professional for a proper diagnosis. Since the CPU is the most essential part of your PC, any damage or a bad chip can stop your computer from starting.
It might turn on, but nothing will show up on your computer. The PC won’t pass the POST test if the CPU doesn’t work. But this can happen for more than one reason.
Before you replace the CPU, we suggest you do what you must to find out if the CPU is dead. Knowing if the CPU is dead before you replace it, you won’t have to spend much money on a new CPU chip.
Common Things That Might Indicate a Dead CPU
When the CPU dies, the system will start up, and the fans will turn on, but the monitor will not show anything. In some cases, the machine may not even turn on.
All of the following things will happen if the motherboard can’t find a CPU or if the CPU on the motherboard is dead.
- The motherboard’s red CPU light will come on.
- Fans will spin as fast as they can.
- Black window
- PC shuts down by itself.
How to Tell if A CPU Is Dead?
CPU chip rarely stops working. The main reasons your CPU is dead are bent pins and physical damage. If the pins aren’t broken, and the CPU hasn’t been physically damaged, look at the whole system before deciding that the CPU is dead.
Even though the above signs might lead you to believe that the CPU in your system is dead, there are a few other things you can do to make sure.
POST Test
POST, “Power On Self Test,” is the first thing the computer does when you turn it on. The test sees if the system can find every piece of hardware it needs. This includes the CPU, the RAM, the GPU, and a few I/O devices.

It can’t talk to the GPU if the CPU doesn’t work. So, there will be no screen on the machine. The system will run, and the fans will turn, but nothing will be on the screen.
You can also put a POST card in one of your motherboard’s expansion holes. The error number will be shown on the POST card. With this code, you’ll know for sure if the CPU is broken or if it’s something else.
Check for Bent Pins
Most of the time, the CPU chips stay intact over time. As you use newer OS and apps, they tend to slow down. Only bent pins can hurt the CPU in a way that can’t be fixed.

Take the CPU off the motherboard and look at the pins to see if they are broken. All of the pins should be in the same direction. Not every processor, though, has pins that connect it to the motherboard.
There won’t be any pins on the Intel process. If you have an Intel processor, you might have broken pins in the CPU socket on the motherboard. But if you use an AMD processor, the pins on the CPU may be bent.
Check Fans RPM
When the computer starts up, the BIOS on the hardware controls how fast the CPU and case fans spin. If the computer doesn’t find a processor, it won’t be able to pass the POST test. So, if the CPU is dead, the fans will run at their fastest RPM.

Follow our guide to fixing CPU fan error on boot
So, if the computer makes a lot of noise, the motherboard doesn’t recognize the CPU.
Replace CMOS Battery
The CMOS stores the date and time, the boot device, and details about all the hardware connected to it. The CMOS battery gives the CMOS chip the power it needs to hold all this information when the machine turns off.
If the CMOS battery dies, the PC might not start up right. Change the CMOS battery to see if the PC will start up.
Re-Insert the Power Supply
When the motherboard doesn’t see the CPU, it could also be the PSU’s fault—the power supply unit’s 8-pin cable links to the motherboard.
The CPU chip gets its power from this wire. A broken 8-pin connection has been known to cause problems like the CPU not being seen by the motherboard. Put this wire back in the PC and turn it on to see if it passes the POST test.
If it doesn’t work, it could also be because the PSU isn’t giving the computer enough power. Change the PSU to see if that solves the problem. If it still doesn’t work, try again to see if the motherboard is picking up the CPU.
Remove and Reconnect All Wires
Your PC may act strangely sometimes because of how it is wired inside. If the wires from the CPU fan are not linked correctly, the fan won’t turn. Because of this, the CPU will run at very high temperatures. So, the PC will shut down at random. Aside from this, it would be best to secure the cords from the PSU.
Try removing all the wires and putting them back in to see if the motherboard can find the CPU.
Check CPU in Another Motherboard
Lastly, if nothing else works, remove the CPU from the current machine and put it into a different one. If this system works, the motherboard from the last build was probably broken.
But the CPU will likely be broken if the new system still doesn’t turn on.
Can I Run a PC Without a CPU?
With a CPU that works, the PC will pass the POST test. Also, since the GPU needs to talk to the CPU, you will only see something on your computer if you have a CPU.
The monitor will not show anything even if the computer starts up and the system or case fans spin.
Test the Processor on Another PC:
When you think your CPU is acting up, the problem may be more likely with your motherboard than your CPU.
If you want to be sure, test your processor on another machine. This is one of the best ways to find out how your CPU is running.
Here are the steps you need to take:
- Disconnect the power cords from both computers.
- Make sure to take out both of the computers’ processors and heatsinks.
- The heatsink and processor should be put back on the test computer, and the power source should be plugged back in. Make sure that the processors in both computers can work with each other.
- Then turn on the computer and watch what happens.
If the BIOS doesn’t load or you hear the same beeping sound as before, your CPU is probably dead.
Why Your CPU Might Die

There are many things that can cause your CPU to die. As an example:
Time & Usage:
The longer your computer has been around, the less likely it is that it has a strong processor to handle more challenging jobs. When a processor hits the end of its useful life, it may not be able to keep up with the demands of modern software and hardware configurations.
Go through our epic guide on How to Remove Thermal Paste
How often and hard you use your computer affects how long it lasts. It may last longer if you use your computer for things like browsing the Internet or checking your email, which doesn’t take much CPU power. But your CPU will wear out faster if you use your computer for more demanding jobs, like editing videos or playing games.
Overheat:
When you’re doing heavy work on your computer or using it for a long time, keeping the CPU cool for better speed is essential. One of the most common ways your CPU can die by getting hurt is if it gets too hot.
Also, check out our separate post on CPU Overheating
Even though most processors today are made to work at higher temperatures, using them for a long time can damage them internally and cause them to break down.Most likely, cheap heatsinks or inadequate air systems are to blame for a hot CPU.
Overclocking:
When you overclock the CPU, you force the machine to work faster than its average speed. This makes the core speed faster. This has a lot of good points, but it can also hurt the chips.
Since boosting requires adding more voltage to the processor, the extra voltage could shorten the life of your CPU.
Go through our epic guide on Should I Overclock My CPU
Electrical Power Surge:
A power surge can be terrible for your CPU and other significant computer parts. It can hurt the whole system, and the current can spike at high rates beyond what your CPU and PSU can do to protect you.
Most of the time, an electrical power surge is caused by lightning or a power loss.
Unstable Voltage:
A voltage that isn’t steady is similar to a power surge in some ways. There may be more than one reason for this, but most of the time, it’s a cheap and bad PSU. These power supplies damage your machine and its parts more than they do good.
Bad Motherboard:
You should know that a motherboard’s main job is to join all of your parts so they can talk to each other. Most of the time, it handles the voltage and current that go through the parts. So, it is easy for a bad motherboard to kill the CPU.
Conclusion
If you do the above steps and your computer fails the POST test, your CPU may be dead.
But before you replace the CPU, you should know that the CPU doesn’t usually get damaged or stop working unless it has a broken pin or a burn mark that you can see. Make sure that the CPU is dead before you replace it.
FAQs
Will PC start with dead CPU?
If the CPU dies, the computer won’t be able to turn on, or if it does, it won’t be able to finish booting up. If the CPU fails, the computer may show a warning message or make beeps to tell you something is wrong.
Can you repair dead CPU?
For a desktop PC, it is often easy to remove the CPU cooler, remove the lousy CPU chip, and put in a new one. Apply the thermal paste, and then put the CPU cooler back on. For a laptop PC, the easiest option might be to replace the motherboard or even the whole machine.
What is the lifespan of a CPU?
In the same way, your CPU will last longer if it is cooled well and not sped up too much. Most likely, the other parts of your build will break before the CPU does. A typical CPU can last about ten years if cared for well and kept calm.
Can BIOS start without CPU?
Even though your CPU and motherboard are physically compatible, the system won’t POST (Power On Self Test, which means all gear works) until you update the BIOS. Your computer might turn on, but the screen won’t show anything because the base doesn’t know how to talk to the CPU.
What causes CPU to fail?
They might give up. Heat: CPUs die when they get too hot. This can happen if the room temperature is usually above 80 degrees Fahrenheit and the computer doesn’t have an excellent way to cool itself down. Overclocking or stress: CPUs are not all made the same.