BIOS is the basic system of any computer, which serves to ensure the interaction of software with hardware and is a low-level firmware stored in a flash memory chip (electrically erasable reprogrammable ROM), connected via SPI interface to the central processor. When the computer is turned on, the firmware from the BIOS is copied to the RAM, and from there its code is executed, as a result of which basic testing and configuration of the components are performed, a loader program is determined, which subsequently controls the launch of the operating system.
Before your OS boots, the BIOS code performs a Power-On Self Test, a procedure for self-testing components after power-on. At this stage, the hardware setup and its performance are checked. If there is an error, a message with its code may be displayed on the screen, an audible signal may sound, or the indicator may blink in a certain way. The number and nature of the signals indicate a certain error.
In 2010, a new firmware standard appeared - UEFI. This is a more flexible system that supports the latest hardware, with a more intuitive and user-friendly graphical interface.
Causes of laptop BIOS firmware corruption:
- During a BIOS update, an intentional or accidental power outage or system reboot occurred and the code was not completely written to the memory chip;
- The BIOS firmware does not match the hardware for which it is provided, and also if the BIOS code has been incorrectly modified by a third-party developer or a virus;
- If the update occurs from under Windows - an operating system failure or software conflicts, for example, blocking the flasher program by an antivirus;
- Failure of the BIOS chip as a result of an electrical malfunction of the motherboard;
- Hidden firmware errors;
- Windows 10, along with updating its components and drivers, may incorrectly update the laptop BIOS, as a result of which it may stop turning on at all or turn on but not display an image on the display.
As a rule, part of the laptop BIOS firmware is damaged, for this reason the symptoms are always different, depending on the firmware block:
- When you press the power button, only the cooler starts, which rotates at maximum speed.
- After turning on, the laptop restarts cyclically. This manifests itself in the form of spinning up and stopping the cooler, as well as turning on and off LED indicators, if any.
- The laptop shows no signs of life. There is no image on the screen. The splash screen with the name of the manufacturer is not displayed.
How to flash or update laptop BIOS:
- Using the official utility from the manufacturer of your laptop directly in the Windows operating system in graphical mode or from the command line.
- Directly in the settings of the BIOS of the device itself, specifying the firmware file on a USB flash drive or HDD / SSD.
- On the programmer, but for this you need to solder the memory chip.
How laptop BIOS is flashed:
Disassembling a laptop;
Removing the BIOS chip from the motherboard with a hot air gun;
Preparing a new BIOS firmware, transferring device serial numbers, OS license keys, clearing the ME region and, directly, writing the corrected laptop BIOS firmware into a flash memory chip on the programmer via the SPI interface;
Soldering the stitched microcircuit on the motherboard;
Assembling the laptop and checking its performance.