What should I do if the computer can't be turned on? The reason and solution for the computer can't be turned on

What should I do if the computer can't be turned on? There are many reasons for the computer to boot, there are hardware problems and software problems. The hardware may be caused by the motherboard or the hard disk. The software may be caused by a BIOS program or an operating system. This article summarizes and summarizes some common and typical startup fault resolution techniques. These are accumulated after long-term experience and I hope to help you.

The reason why the computer can not open the machine and the solution

1. How to solve the problem that the computer is not powered on

A newly installed computer, after pressing the power button, the display No display, the power indicator does not light, and the computer does not start.

Inspecting such faults, you should first check the connection problem, and then check the accessories for good or bad problems. The specific steps are as follows:

First observe the monitor power indicator and find the indicator light constantly. Blinking, indicating that the monitor power connection is normal, and then replace the host power cord, the fault remains, indicating that it is not a problem with the power cord.

Unplug the mains power cord, then open the mainframe chassis, unplug the ATX power plug, re-insert the motherboard power socket, and then boot the test, the fault remains.

Check the chassis power switch line and find that the switch cable is connected to the PW-ON pin on the motherboard, which is completely correct, as shown in the figure.

At this point, it is suspected that the power supply is faulty. Replace the original power supply with a good power supply, and then start the test. The display shows a startup screen to confirm that it is a power failure.

After replacing an ATX power supply, install the operating system and test it with the test software. Everything is normal and troubleshooting.

Power

This type of failure occurs mostly in older computers due to damage to the ATX power supply, or damage to the motherboard, or problems with the chassis power switch line. Most of the newly installed computers are caused by the plugs not being plugged in or the wrong position of the switch wires, but it is also possible that the ATX power supply is damaged or the motherboard is damaged.

2. There is no display after the computer is turned on, but what if the main unit power indicator is on?

Phenomenon: After the computer is turned on, the display does not respond. The power indicator of the host is on and cannot be activated.

Remedy: When checking such faults, check the connection of the signal cable of the monitor first. Check the accessories. The specific operation is as follows:

(1) First check whether the display signal is Good contact.

(2) If there is no problem, unplug the main unit power cord, then open the chassis to check if the memory, graphics card, etc. are in poor contact.

(3) If the memory, graphics card, etc. are installed firmly, then use the replacement method to check the memory, then boot detection, and find that the fault disappears, so it can be determined that there is a problem with the original memory. Replace a new memory and troubleshoot.

New computers are generally prone to failures in the installation or incompatibility of the accessories. If there are conditions, it is best to use the replacement method after the problem occurs.

3. What should I do if the computer does not boot?

Phenomenon: After pressing the power button of the chassis, the monitor is black and the power light is flashing. After a while, the computer does not start.

Solution: According to the analysis of the fault phenomenon, this fault may be caused by the shutdown signal after the computer is started or the motherboard does not have the boot condition, such as the motherboard CPU power supply problem (the motherboard power supply circuit is faulty), the motherboard Short circuit, etc. You should first check the power-on button and its connection cable, and then check the ATX power and motherboard problems, the specific operation is as follows:

(1) Check the host power-on button and find that the button is inferior.

(2) Open the mainframe chassis, unplug the computer's power-on button and the reset button, then short-circuit the power switch of the motherboard, the computer can start normally, indicating the motherboard of the computer and There is no problem with the ATX power supply, as shown.

(3) Carefully check the power switch spring and find that the spring fails. After pressing it, sometimes it will take a while to bounce slowly, so the motherboard will be turned off immediately after booting. After repairing the power switch, start the test and troubleshoot.

4. Why can't I start after the computer is shut down illegally

Phenomenon: The computer can't start after the computer is shut down illegally, the indicator light is on, there is an alarm sound.

Solution: According to the analysis of the fault phenomenon, it may be caused by an illegal shutdown. Since the computer has a BIOS alarm sound, the fault can be found according to the alarm sound. Should listen carefully to the alarm sounded by the BIOS, then check the type of BIOSD, and then look for the fault according to the BIOS alarm sound law against the BIOS alarm sound table, as follows:

(1) Boot, find the computer issued a long nine Short continuous alarm sound.

(2) Turn off the computer, unplug the power cord, open the chassis, check the BIOS chip of the motherboard, and find that the BIOS is the Award BIOS.

(3) Check the BIOS alarm fault table to confirm that the alarm sound is FLASH RAM or EPROM error, that is, the BIOS program is damaged.

(4) Discharge the BIOS on the motherboard (can be discharged through the jumper), restore the BIOS program to the factory defaults, and then re-connect the power cord to start the test, the alarm sound disappears, and the fault is eliminated.

If the motherboard has an alarm sound, it is generally necessary to find the fault based on the alarm sound. But sometimes the BIOS alarm sound is not the faulty component itself, and further troubleshooting is required.

5. After cleaning the computer, what should I do if I turn on the black screen and accompany the constant alarm?

Phenomenon: After replacing the fan of the computer CPU, the dust in the main box is cleaned up by the way, and there is an alarm sound when the machine is turned on.

Solution:

(1) Turn on the computer and find that the computer has issued a long three short alarm.

(2) Turn off the computer, unplug the power cord, open the chassis, check the motherboard BIOS chip, and find the BIOS as AMI BIOS. In contrast to the BIOS alarm sound failure table, this alarm sound is a memory error.

(3) Unplug the memory, then wipe the memory gold finger with the eraser, re-plug it, then connect the power cord to start the test, the alarm sound disappears, and the fault is eliminated.

Before cleaning the computer, unplug the main unit and remove static electricity from your body. After cleaning, it is best to check carefully whether the memory, graphics card and other components are plugged in to prevent contact problems caused by cleaning.

6. What's going on with the newly installed computer booting black screen

Phenomenon: This type of failure occurs in newly installed computers due to compatibility problems between hardware or hardware not installed and poorly connected. Caused. You should first check the monitor signal cable connection problem and then check the accessory problem.

Workaround: The steps are as follows:

(1) Check the monitor signal cable for good contact.

(2) Unplug the main unit power cord, then open the chassis, check the memory, graphics card, etc., no bad contact.

(3) Check the computer with the minimum system method and find that the fault remains, and the hard disk and optical drive equipment can be eliminated.

(4) Check the memory and graphics card with the replacement method, and find that the computer is turned on normally after replacing the graphics card. Then check the original graphics card and found that there is an external power supply cable on the original graphics card.

(5) Reinstall the original graphics card into the computer, then plug in the power cable of the graphics card, and then boot the test, the fault disappears.

This article summarizes some common and typical startup troubleshooting techniques. If this article fails to solve your problem or has some questions, you can post in Pepsi Q&A (ask.pc841.com) We have a question and answer.

If you are a notebook user, you can't open the machine, please refer to: "The reason and solution for the notebook can not open the machine."