This is a very rare case that some users experience that the computer turns on automatically when plugged in .The computer turns on automatically when plugged in without pressing the Startup switch located in the cabinet.This type of problem can prove to be very disastrous for your computer as it can create severe problems for the hardware especially the Motherboard causing burnout of motherboard . Also there are chances of losing valuable data from the hard disk so it is highly recommended that you should backup your important data when you start experiencing this kind of problem.When you plug in your computer you will experience that all the cabinet and PSU (Power supply) fans are running and motherboard light is also on but there is no display on the Monitor until you actually press the Startup switch on the cabinet.Also during the shutdown process you will find that after shutdown process still all the cabinet and Power supply fans are running and motherboard light is still on.This problem must be resolved before it could cause some serious damage to your hardware parts.This problem can arise due to various reasons but most common reasons are given below with proper solution.
Reasons for This Problem ( Computer turns on automatically when plugged in ):
Faulty PSU(Power Supply) – A faulty PSU can be the culprit of this problem .Generally this kind of problem arises due to a faulty Power supply.Power supply causes this kind of problem when its wires are getting shorted somewhere and thus causing an automatic startup after plugging in. You can test your Power supply by performing a paper clip test of Power supply.
Faulty Motherboard – A faulty motherboard can also cause this problem by shorting the 24 pin power supply wires . So make sure that all the power cables are properly placed in the motherboard so that it should not short the power supply.
Bios Problem – Check all the bios setting of the motherboard and check the power options located in the bios option and make sure that the power option in the bios is set to stay off in all the conditions.
Faulty Cabinet Startup Switch – Shorting of wires at the Cabinet startup switch can also cause this kind of problem.
* If you experience computer turns on automatically when plugged in with a beep sound than it can be a problem of a faulty RAM or hardisk .
Fix Computer turns on automatically when plugged in
- Check your power supply by performing a paper clip test because if a power supply turns on after plugging in without actually shorting the wires then it is a faulty power supply so replace it as soon as possible. You can perform a paper clip test by seeing the below video demonstrating how to perform a paperclip test on a Power supply.
- Check all the wiring’s near the start up switch and make sure that they are not shorted .
- Also check the Power settings in the bios and make sure that the power option in bios is set to stay off in all the conditions.
- If power supply , start up switch and bios are all ok then it is all due to a faulty motherboard .
* Also make sure to check your RAM and hard disk Separately
I have a similar problem, but it only happens when I have my video card plugged in.. Even without it though I hear short beeps. Probably a hd failure, but it’s mostly video card. Do I have to buy a new one? Or is there something I can do about it?
Beep sounds basically indicates RAM Issue..Have you checked your RAM is it good ??
RAMs are ok, I moved them to another computer and checked them and they had no problem there.
Had similar problem when powered up workroom. Changed CMOS battery – CR 2032. All fine now.
Cheers from Scotland,
Gordon.
How can I solve if the problem on the motherboard?
If the motherboard is faulty then you have to take your motherboard to the respective service center….You can’t do much R & D with your motherboard and its not advisable to do as well if you aren’t technically aware about everything on motherboard….Thanks
This thread is old, but I thought I’d comment anyway. There were two things I learned in trying to track down my “power on at plug in” problem that started when I got the computer back from a computer repair store.
One was that my Acer desktop running Win 8.1 wouldn’t let me get into the BIOS to check the power settings. I pressed F2, F12, F11, Esc, etc but it wouldn’t go. A buddy of mine suggested letting it boot up and then shut it down by doing a “Restart” but when you click on RESTART also press the SHIFT key. This gets you into the screens that eventually get you to Troubleshooting where you can navigate to the BIOS.
HOWEVER, once in the BIOS screens I couldn’t get the keyboard to work. I quickly plugged in a WIRED keyboard and it worked fine. I changed a couple of the POWER settings and it works fine now.
My pc is starting directly without switch on power botton in front panel or cabinet. I changed my PSU after that also i am getting this problem.At the same time I am getting another problem i.e. The firmware has detected that a CMOS Battery faliure occurred. i Have Intel 945 GNT Motherboard.if its require bios setting after changed CMOS battery, then tell me the step as per Intel 945 GNT motherboard BIOS.
The problem is the switch is not functioning anymore and want to make It automatic on when I plug it to power and it will on it lself