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PC doesn't boot after OC - only if i unplugg PSU

Hello guys,

before i ask, here are my specs:
Intel 6700k
MSI Z270 Gaming M5
Kraken x52 AIO CPU Cooler
MSI R9 390x (which was not installed once)
RAM: Corsair Vengeance Led 3000 Mhz (2x8Gb)
PSU: EVGA 650 GQ

I just recently build my first pc and after installing windows and some basic programs, I thought i can start to overclock my CPU, before I install more program. so i went to the bios and set the cpu core multiplier to 46. Bclk was all the time at 100. Voltage was at default about 1.32V, but i had to increase the Voltage up to 1.35V, which isn't that high for me. Temps were absolutly fine. idle: 25-28 and under heavy stresstesting (cinebench,prime95 (26.6v) and realbench): 67-70. so i set the cpu core multiplier to 47 at 1.35V. everything was fine - again. the temps were similar. i run realbench for 1 hour and everything was fine. and than i wanted to aim the 4.8ghz to see if it work in my system. and since i did that, my pc doesnt boot anymore properly. of course i set everything back to default. but still at default bios settings, my pc doesnt even react if i push the power button. it only boots if i unplugg my psu cable for 1 min. i tried to remove 1 RAM stick, nothing changed. if i push the clr-cmos button, it takes the bios to default settings, but after i hit "save & exit" the pc shut down and doesnt want to boot.

this is the first time i tried overclocking, and i read a lot about OC before i tried on my own pc. is it possible that i somehow damaged the psu? I am glad about any help.

(Btw - sorry for my english :D )
5 answers Last reply Best Answer
More about boot unplugg psu
  1. Quote:
    but still at default bios settings, my pc doesnt even react if i push the power button.
    Quote:

    it only boots if i unplugg my psu cable for 1 min.. if i push the clr-cmos button, it takes the bios to default settings, but after i hit "save & exit" the pc shut down and doesnt want to boot.


    Both those statements make me consider it is not the PSU the issue. you can do the paper clip test on PSU and find out. also when you pres power and unit does not boot, the fan on PSU does it spin?

    When you press clear-cmos on the motherboard and it permits you to power up to bios (and that is normal) tells mes your problem is more likely your motherboard that is having an issue. if you clear cmos and set a mild OC on the system and you save/exit, does it reboot properly ? if not I would get your Board exchanged.
  2. Thanks for the answer! If I press the Power button the fans wont start to spin, it doesn't happen anything. if i go to the bios by pressing the clear cmos button and if i set a mild OC or even if i set the default settings, the system turns off after hitting save/exit and it doesn't boot up again. Only if i unplugg the AC Cable of the PSU for 1 min.

    EDIT: it is weird - i unplugged the AC Cable from my PSU overnight, and today after i plugged it back and pushed the power button, nothing happens. i have expected that it will boot after the PSU cable was unplugged for so long.
  3. I would test the PSU first its easy (paper clip test) http://www.wikihow.com/Check-a-Power-Supply
  4. I just tested the psu and the fan doesn't spin. i tested it in both "modes" - normal and eco. in both the fan doesn't spin. so i gues i just killed somehow my psu. at least its not that expensive than a new motherboard.
    Thank you for your help!!! But how can OC kill a the PSU ?
  5. Best answer
    it is possible how old is this PSU, you could exchange it at store if allowed, if not old, then you could get a temp patch psu and yours get it warranties by EVGA
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