Computer wont turn on? Can someone help?

I had an update on my computer and after it updated fully then restarted it stopped turning on. What could be the issue?

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Well when I tried to push the power button nothing happens at all not even a flicker. When it updated it went to my desktop and said it had to restart one more time, but when it shut off it didn't turn back on. I assumed it was the PSU but could it be a hard drive issue also?

check your cables.  Make sure everything is plugged in securely.  Could be a PSU issue (or a problem with the power switch), but I'd check cables first.

I doubt it is the HDD or even has anything to do with the update if you are not even getting lights or fans. Problems I could think of would be (in no particular order) dead psu, loose power cable (both to the wall and inside the case), dead mobo, dead cpu, bad ram, short inside the case (maybe a loose screw fell between the case and mobo), tripped circuit breaker (make sure if you plug something else into that same outlet you get power), front panel connector from your case to your motherboard is loose or your power switch is broken (if you suspect the power button is broken use a flathead to try and jump start your pc). It's probably one of those, it's really hard to diagnose this kind of issue remotely.

May not fix it, but first thing i always do when a pc that should turn on doesn't. Remove all sources of power from the power supply (on laptops also remove the battery), and then hold power switch for 10-15 seconds to drain any residual power. This effectively "resets" the components on the m/b. Then plug all power back in and test.

oh and if you suspect it may be another component causing the issue, remove power from that component and then try to post. You can still post with no hdd, no graphics card, no fans, no case. All you HAVE to have is M/B, processor, and a power supply. if it turns on consistent with just those 3 elements then it is one of the other components.

I always thought you needed ram to post.

Depends on what you are going for. I wasn't very clear with that. You will "post" without RAM, but you will get whatever post code signifies "no ram." This is simply a way to test "Are my motherboards alerts and error codes working properly." If you post with no ram and you don't get the appropriate code - most likely m/b took a shit on ya

 Is it turned on at the wall? Sorry but I had to ask.

A software update cant really nerf a system that bad that it fails to post > it will be a hardware fault, power issue or a short somewhere. Go through the normal testing procedure as mentioned above, outside of the case - barebone motherboard + cpu + 1 stick ram + keyboard + monitor + gpu if no onboard video is available, nothing else.

Okay I jump started it and it turns on but my processor fan isn't spinning and there's nothing on my monitor. is my cpu/motherboard dead?

I got a brand new PSU and tried to start it and it wouldn't work. I had to jump start it doing the motherboard, 1 stick ram, and cpu and nothing came on at all


Also my brand new graphics card's fan isn't working. I am just assuming at this point that the motherboard is dead.

Of course can't be 100% certain when I can't work on it myself, but it does sound like motherboard.

Okay well thanks for all the help!