Your computer is dead. It will not boot. It was working the night before, but now when you hit the power button nothing comes up on the screen. But is your computer really dead? Or is it giving off subtle clues as to why it is no longer functioning normally? Below are some generic and model-specific diagnostics that demonstrate how a computer can be trying to communicate its problems to you.

Computer Beep Codes

One of the most common ways for your PC to communicate to you during a hardware issue is through a beep code. Your computer’s BIOS will often produce an audible beep code to indicate why it is not working. If you have a custom build and are not receiving a beep code, make sure your motherboard has a speaker attached to it as not all cases come with a speaker you can plug directly onto the motherboard.

Note: This is not an external speaker you plug into the back of the computer, it is a speaker that plugs onto the motherboard itself.

If your computer is producing a beep code, the next thing to determine is what kind of BIOS is running on that computer. If your PC is not displaying anything at all on the monitor, you may need to resort looking directly on the motherboard for the BIOS chip.

award bios

A few common BIOS manufacturers are AMI BIOS, Award, and Phoenix, and here are their BIOS beep codes.

Computer Diagnostic Lights

Some major brand name computers such as Dell, Lenovo and HP can communicate via diagnostic lights on the case, power supply or on the power button itself. The best way to determine what your computer is trying to say through these diagnostic lights is to visit the website of the computer manufacturer and read its online manual. For example, the Dell Optiplex 9020 uses a front power button diagnostic light that flashes when there is a hardware problem.

Dell power button amber light flash codes:

2 pause 1 – This indicates a system board failure

2 pause 2 – This could be a bad system board, PSU or PSU cabling problem.

2 pause 3 – Possible system board, memory or CPU failure

2 pause 4 – CMOS battery failure

2 pause 5 – The computer has a corrupt BIOS

2 pause 6 – CPU configuration failure or CPU failure

2 pause 7 – Your memory modules are detected, but there is a memory failure

If your Dell model has diagnostic lights on the rear of the computer, refer to this article on Dell diagnostic lights to determine the problem. If you have a different make computer, go to the manufacturer’s website support section and search for the manual for your computer manual.

Onboard UEFI Diagnostics

Your computer may have a Unified Extensible Firmware Interface (UEFI)–an advanced BIOS replacement–capable of running diagnostics.  If you have a Dell, HP or Lenovo computer, for instance, restart the computer and begin tapping the F12 (for Dell), F2 (for HP) or F10 (for Lenovo) keys to launch the diagnostics. These diagnostics can tell you if there is a problem with your computer hardware.  Below is a screenshot of a Dell diagnostic page:

dell diagnostic

If your major brand name computer does not have this functionality, you can create a bootable disk to run these diagnostics.

Download Lenovo diagnostics here.

Download the Dell diagnostic disk here. Type in your service tag (serial number) and then select the diagnostics drop down to download the disk.

Download the HP Diagnostic disk here.

In Conclusion, your computer is machine destined to fail. Make sure you know how to obtain and run diagnostics on your computer when that time comes. Use the above methods to run computer diagnostics and if your computer does not have that capability, find a way to obtain the bootable diagnostic disk necessary to run them.