Computer flickers then turns off after powering on.

[Richard Webb]

After working perfectly fine yesterday, I turned on my pc today and it seemed to post normally except I had no display. After turning off and checking my HDMI cable I started it again, all fans and lights turned on for a split second and then turned off.

I'm using: [i7 8700k (overclocked to 5.0ghz), asrock fatal1ty z370 itx mobo, evga gtx 960, 1000w bronze cooler master psu, 2x8gb corsair vengeance lpx ddr4, samsung 850 evo, toshiba 7200rpm hdd, windows 10 education].

Since then, every time I startup my pc, it turns on for only a split second before turning off.

Will I need to rma my motherboard/CPU? Or is there a solution that I'm not seeing? The only old part in my build is the PSU which I got used and I think is over 4 years old, everything else is relatively new, my main concern is whether the old psu has damaged the mobo.

 

What I've tried: (No change whatsoever after each)

- Removing all expansion cards and peripherals

- Clearing CMOS

- No damaged capacitors

- Double checked 24 pin and 8 pin connectors 

- No obvious shorts

- Took motherboard out of case

- Tried different RAM, PSU, CPU fan

- No bent socket pins or burnt cpu contacts

- Reseated CPU and RAM

 

Hopefully there's something I'm missing, is there anything else to check? Also is there any way an old PSU could damage components even when the computer is turned off and surge protected?

Any help is appreciated.

[Astarore]

When you hit the power button,do you hear/see the PSU turn on/cut out immediately? If you do,that could mean the PSU is doing it's job correctly if something is drawing too much power (aka a component is fried) and cutting out to prevent damaging components.

[Richard Webb]

2 hours ago, Astarore said:

When you hit the power button,do you hear/see the PSU turn on/cut out immediately? If you do,that could mean the PSU is doing it's job correctly if something is drawing too much power (aka a component is fried) and cutting out to prevent damaging components.

Yeah, the PSU powers on, the fan spins for a second and then cuts out. If that's the case, is there an easy way to tell what it is? I don't have another motherboard or cpu to test with. 

[Fulminatrix]

You can check your power supply by unplugging it from motherboard and shorting two contacts (PS-On and Ground) in 24-pin connector as shown in the picture. Connect something like cdrom to your power supply. Then turn on the PSU. You'll see if psu is working.

[Wyldist]

Hmm youve tried dicferent ram, but heres what I would try again. Power on and clear cmos immidiately. Remove all ram and clean ram slots with makeup/paint brush and conpressed air, or the best tools you have available. Insert one stick of ram in the corrext slot as stated by your motherboard manuel. Manually UNPLUG all power and I mean ALL power cables. Unplug and reseat gpu while youre at it. Replug cables. Try again and see if anything changes. My gut says its ram issue though.