If the computer stops responding to pressing the power button, or, after turning on, does not display anything on the monitor screen. Do not rush to call the master - it is quite possible that you will cope with the malfunction yourself.
Instructions
Step 1
First of all, don't panic. With this type of malfunction, it can be said with almost complete certainty that the cause of what happened is not a failure of the hard disk. Even if you fail to start the computer, you can always remove the hard drive from it and rearrange it to another machine, and then transfer all the data that is valuable to you to it.
Step 2
Check the condition of the switch located directly on the power supply. It could be accidentally pressed, for example, by a cleaning lady. If this is not the case, unplug the power cord from both the computer and the outlet, then check with an ohmmeter. If it turns out that the cord is also intact, try connecting another load to the same outlet - at least a table lamp. If it turns out that there is voltage, the cord is intact and the switch is on, try starting the computer with a different power supply.
Step 3
If the computer starts up (immediately or after replacing the power supply), but nothing is displayed on the screen, and the speaker, which usually emits a short beep when turned on, is silent this time, then the motherboard is out of order. And it was the previous power supply that could “pull it along”. Measure the voltage between its lilac and black wires - if it is not 5 V, but from 8 to 9, then the unit not only failed, but also damaged the motherboard. Simultaneously with its replacement, replace the power supply, if you have not done so earlier.
Step 4
Sometimes the power button located on its case becomes the reason for the inoperability of the computer. There are two wires from it to the motherboard. Disconnect the appropriate connector from the board and close the contacts with a screwdriver. If it was possible to turn on the computer this way, but it does not respond to pressing the button, connect the Reset button instead, and then warn everyone who uses the machine that it is now necessary to turn it on with this button.
Step 5
Constant freezes and malfunctions of the computer (sometimes even at the BIOS boot stage) with a fully functional hard disk are caused by dust (including under the motherboard), as well as faulty RAM modules (DIMMs). Test them first using the Memtest86 + program. If necessary, replace the faulty module by first disconnecting the machine from the mains. If it turns out that the matter is not in the memory modules, also unplug the machine from the network, then disassemble, remove dust from the slots and from under the motherboard, then reassemble.
Step 6
A malfunctioning hard drive is characterized by an unusual knocking noise during its operation, failures during loading and when launching programs. If the computer stops booting for this very reason, connect an external hard drive to it, boot the machine from a Linux CD (Dr. Web Live CD will do, in particular), and then transfer the data that you can read to the external medium. Then replace the hard drive and reinstall the OS.
