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Question

PC repeatedly turns on and off for half sec. Not pressing PB

Mar 23, 2018 12:21PM PDT

So the problem is the following. I was playing some games on my PC and it just shut down for no reason. Then it started turning on and off by itself for several times and then I shutted it down myself. Then this happens: Once my PC is plugged on the power and while the power supply is on, the PC tries to turn on by itself and then shuts down immediately. Not even for 1 second. I can barely see the led lights turning on and then they are off. I can hear the click that means the PC is turning on but nothing happens. All by itself. This loop happens every 7-8 seconds and it keeps happening unless I remove the cable or turn off the power supply. I have no idea what is this. Pls help

Setup:

i7 7700K 4.2
Asus rog strix Z270E gaming
Titan XP star wars edition
32GB RAM corsair vengeance 3000mhz
Coolermaster 1200W 80 plus platinum

Discussion is locked

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Answer
Looks self made.
Mar 23, 2018 12:28PM PDT

The usual advice is "Make it smaller."

You don't need the GPU as the i7 has graphics. The motherboard has video ports too.
You don't need more than one stick RAM.

If that doesn't bring it back then remove the case and put the bare min parts on cardboard for testing.

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Hardware/Software
Mar 23, 2018 2:18PM PDT

So is this definetely a Hardware problem? And if so it could be anything right? Couldn’t it be something else like a broken power button or so?

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At seconds of power on.
Mar 23, 2018 2:23PM PDT

No OS is running. You could try resetting the CMOS values but I didn't read if you were OVERCLOCKING so I didn't mention that.

If it is a power button, then unplug that and use a pen tip like you see techs do on the posts for power on.

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Not overclocking
Mar 23, 2018 2:27PM PDT

Not overclocking. Could it be the mobo’s battery?

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Sure. But would be rare.
Mar 23, 2018 2:34PM PDT

Never saw this issue traced to a battery but here's a thing. It could fix it if it's one of the more common reasons. That is I continue to find self built machines (not a bad thing!) with extra mounting posts. These will work for some time and confuse the heck of the owner as we want to pull the motherboard out. "It worked for years!"

The usual is to downsize until it works. Sometimes you find loose screws inside the case (really loose, just sitting there on the motherboard.)

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Didn't finish that thought.
Mar 23, 2018 2:40PM PDT

I've seen a battery fix it. But it failed again and we found the usual extra post. What we think happened is when the new battery went in the motherboard change position, the short went away and it worked. It was never the CMOS battery.

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Ordered a mobo replacement
Mar 24, 2018 1:11PM PDT

Ok noted. So I already ordered a mobo replacement and I hope this will solve the issue. The problem existed even with 1 stick of RAM and without the GPU. I will let you know

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CMOS
Mar 26, 2018 11:52PM PDT

So I have tried clearing the CMOS. Not only it didn't fix this, but now I even lost display on my monitor. I have tried connecting it on my Mobo, still no display. I have ordered an RMA for mobo and psu. Shall I order for RAM memory as well? I guess the PC needs to be built all over again.

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Did you make it as small as possible?
Mar 27, 2018 9:17AM PDT

No case, just motherboard and the few parts to get a display?

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Yes
Mar 27, 2018 9:22AM PDT

I ran the pc without the GPU, with only one stick of RAM and got no display. Anyhow I asked for an RMA of both the mobo and the PSU. I am just concerned if this could be a RAM problem so that I ask an RMA for that too

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Why is the RAM suspect?
Mar 27, 2018 12:50PM PDT

With 32GB that's not a single stick and unless there was smoke from the machine it's rare to see all the sticks fail.

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I am just concerned
Mar 28, 2018 6:27AM PDT

I possess 4x8GB RAM. I did ran the PC using only one stick however the issue was still there. I am just brainstorming. Could it also be the RAM memory malfunctioning and leading to this?

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Yes.
Mar 28, 2018 8:38AM PDT

But unless it did this from day one (which points to incompat ram) or later with smoke from the parts, it's so unlikely to be RAM.

But if you ask if there is a chance then yes. But in my experience rarely is unless the parts were smoked.

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Ram
Mar 28, 2018 8:51AM PDT

Remove all the ram.
Does it still do this power up and down?
If so it's doubtful you have a ram problem.