Computer turn off and on repeatedly

Eliasu

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Mar 21, 2013
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ive had my custom built computer for half a year now,without any problems.
earlier i was gonna put in my old hard drive to my computer,which worked some minutes until the CPU fan stopped working.I replugged the fan and it vent full speed some seconds,which was fast enough that it cut my finger :p
then it stopped completely until i replugged it again and the same happend...
i really didnt know what to do so i turned off my computer,because i was going to change the CPU fan.and i did,when i turned it backon it run for like 10 secs and then it turn itself on,and off repeatedly.Ive made sure all the wires are fully connected and they are.Ive also removed the hard drive which started all this...
and still it only turn off and on...i think its the power box,but do anyone know what it is and how i can fix it? :p REMEBER:im not very experienced with computer's and stuff,so please explain good and dont use those high-tech words :)

SYSTEM SPECS/PARTS:
Intel® Core i3-3220 Processor 3,3GHz
XFX ProSeries Core Edition 550W PSU
MSI B75MA-P45, Socket-1155
Kingston ValueR. DDR3 1333MHz 8GB, CL9
ASUS Radeon HD 7870 2GB GDDR5
Sony Optiarc DVD±RW Writer, AD-5280S
Western Digital® Desktop Blue 500GB
MS COA Label Windows Home Premium 7 64bit
 

Feldmarschall

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Mar 9, 2013
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I had same issue. Some of the componnets is mailfunctioning. In my case was video card dying. This is normal repsonse of motherboard when complete current cycle can't be completed. You can try to discharge your capacitors by pressing and holding power button when unplugged. Remove your hard drive (if not yet) cause it may be draining more power than it should (short cuircut somewhere). If that does not succeed than try removing components one by one until you get normal boot.
 

Eliasu

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Mar 21, 2013
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i found those little switch which restarted and cleared cmos and bios,and i got my computer on and running worked fine,and then i turned it off to install the CPU fan which wasnt working earlier.When i started the computer again it turned itself on and off....
I tryed to clear cmos and bios again,but now that wasnt helping ether! D:
 

atomicWAR

Glorious
Ambassador


that's your hint right there. your cpu fan...it's most likely the motherboards fan connector. try a different fan port on the board like a chas_fan and see if it works then. if not your mobo's fan ports are fried and you need to get a psu adapter to turn one your 4 prong plugs into a fan plug.
 

Eliasu

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Mar 21, 2013
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i got the beeps when it worked normally.
ive tryed my old psu and it didnt even have half of the connections :p so the screen card lighs was red and the fan was going but the light on the fans didnt work,and it turned itself on and off like always so im not sure if it is the psu.ive tryed the CPU fan on other port,and it fixed the fan ;)so the fan isnt the problem...but it still turns on and off like always.Ive ordered new cpu and psu now
 

Eliasu

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Mar 21, 2013
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and even to turn it off,i have to hold down the restart button,which is the button next to the start button and turn on and off the power button which is on the backside of the case...
 

atomicWAR

Glorious
Ambassador
also you could try pulling the motherboard from the case and laying it on static papaer if you have some. plug in the psu and only the fan/ cpu, vid card and ram all outside the case. see if it boots. if it does you motherboard was grounded causing you the issues...if not...were back to the PSU or motherboard being faulty