It would be ideal if PCs worked fine forever, but the reality is that there are times when they seem to crash for no apparent reason. However, we still tamper with things, change settings, and install programs that may alter its operation…even if what happened is a hardware issue. Let’s see what you can do about it.
The PC turns on but turns off by itself, why?
The reasons why the PC turns on but turns off after a few seconds can be many, but what we can tell you is that if the problem is exactly this (it turns on and after a few seconds , shuts down even before POST), normally the power supply isn’t the problem, as power related issues usually have different symptoms, such as the PC staying on with the fans spinning but not doing nothing, or does not turn on at all.
The reason why this issue can occur is usually related to two basic issues:
- The processor is incorrectly installed on the socket.
- A short circuit occurs in the system.
In both cases, the problem is usually caused by a shock or a mechanical movement in the PC (to understand each other, whether you moved it from its site or it was bumped), but fortunately in the Both cases there is also a relatively easy solution (although it can be laborious).
How to solve the problem
It is difficult to know which of the two possible situations you are in when the PC turns on and then turns off by itself, since the computer does not go through POST and therefore no error message is seen, usually even not on the code light error panel that many motherboards have, simply because there is no time. So unfortunately the best solution to this problem is to completely disassemble the PC and then reassemble it.
Our recommendation is that after disconnecting all cables from the PC case from the rear, you start by disconnecting all internal cables, first removing any “peripheral” components such as the graphics card or hard drives, leaving the base motherboard for the latter. In this case, since we don’t know if the problem is a short circuit or the processor, it would also be necessary to disassemble the heat sink and even the processor itself, to ensure that when reassembling it is perfectly in contact with the socket.
By the way, since you are removing all the components (in addition to the fact that you may have a short circuit in the equipment), it is also a good idea to do a general cleaning inside the PC, because in addition to be good at improving airflow, reducing noise and increasing component life, you must remember that dust turns to soot with heat and is an electrically conductive substance which could be the cause of the short circuit.
Once everything is disassembled and cleaned, we advise you to make a temporary assembly out of the box and see if it lights up. If all goes well, reassemble everything again and problem solved; if not, it is possible that either you did not install the processor or RAM correctly, or that there is a defect in one of the components and then you have a more complicated solution (in this case you should try the trial and error component to the component).
