Hi folks,
Struggling with a bizarre power issue on a very new PC which has got me stumped.
Spec:
i5 6500
2x 4GB Corsair Vengenace LPX DDR4-2133
250 GB Samsung Evo SSD
R9 390
Gigabyte H170-D3HP
550w EVGA SuperNova GS
PC was built end of January with no problems and has been running like a dream until this morning. Machine powered on, bios screen showed and then there was a clicking noise and the machine shut itself off and back on again. It stayed on for a few more seconds before again clicking and turning off. It turned itself back on again and stayed on but with no source on the monitor. I powered off the machine and after that point the machine did not react to the power button being pushed. The graphics card light and network lights were both still functioning. After coming back to it this evening and press power on it repeated the exact same cycle as above and for a period of about 15 minutes didn't respond to the power button.
I have disconnected everything so that there is just the cpu, cpu fan and psu and the power and hdmi cables and the machine is powering on more consistantly now but still no source with onboard video. On power on it seems to be again turning itself off after a few seconds and then starting up again and staying powered on only on that second attempt.
I have also taken the CMOS battery out, disconnected all the power cables and re-attached them, and checked all the other cables to ensure they are connected with no resoloution.