Question PC turns on but monitor and peripherals have no signal

[uknowumoe]

Hi,

after reading through a few threads and trying things with no success, I'll try it this way.

My system looks like this:

• CPU: Intel i7 8700k
• RAM: 16GB (2x 8GB) G.Skill Trident Z DDR4-3600 DIMM CL17-18-18-38 Dual Kit
• Mainboard: ASRock Z370 Extreme 4 Intel Z370 So.1151 Dual Channel DDR4 ATX Retail
• PSU: 650 Watt Seasonic FOCUS Plus Modular 80+ Gold
• Case: bequiet! Pure Base 600
• GPU: MSI 1070 Ti
• HDD / SSD: 1 GB HDD, 1 GB M2 SSD, 256GB SATA SSD

I've built it myself around 5 years ago and didn't have too many problems (until now).

It started today, when I came back home and was about to turn my PC on, it was already running, even though I shut it down last night.
The monitor does not have get signal and the peripherals (mouse, keyboard, microphone) aren't running either.
Fans and the few leds inside the case are working though.
The only way to shut my PC down is to either use switch on the PSU or to pull the power cable. When switching it back on or plugging the cable back in, it just gets back to this powered on state.

Since then I've tried the following:

• Unplugging the GPU to run on the CPUs integrated graphics
• Using just one of the 2 RAM sticks (tried with both of them)
• Using another, old PSU
• Unplugging most of the things connected to the mobo
• Resetting CMOS (not quite sure if that's how it is called, but I removed the battery and used a paperclip between the two pins - don't have the cap for it)

Nothing has worked so far, it just turns on and does nothing.
I've just ordered one of these beeper things to connect to the mainboard, hoping it might have something to say.

Is there anything else I could try?

Would appreciate any help.

 

[th3reaperskullpt]

We assume when you turned off the PC, the computer could be doing some process of something, when you turned it off you interrupted the "process". Some of this information / data may be blocking the computer from starting, this data is often stored in the RAM memory cache.

Try these things.
- Remove the disks and try again.
- Remove all cables from your computer case to the motherboard, just leave the Power and Reset cables connected to turn the PC off and on.
- Remove the RAMs, and just put one in a different slot.

 

[uknowumoe]

We assume when you turned off the PC, the computer could be doing some process of something, when you turned it off you interrupted the "process". Some of this information / data may be blocking the computer from starting, this data is often stored in the RAM memory cache.

Try these things.
- Remove the disks and try again.
- Remove all cables from your computer case to the motherboard, just leave the Power and Reset cables connected to turn the PC off and on.
- Remove the RAMs, and just put one in a different slot.

Well, I guess I narrowed it down.
The speaker arrived today. I took the mainboard out of the case and the only things I kept plugged in it were the CPU, CPU fan, the speaker and the power cables.

Plugging it in, I didn't even have to short the pwrbtn pins, it just started up once it had power again. Result was the same as before, led on the mainboard turned on, CPU fan started spinning, but no beep at all.
So I'd say it comes down to the CPU or the mainboard itself. Otherwise it should've beeped because of the missing RAM.

Since I was thinking about upgrading / buying a new PC anyway, I guess I'll go this route. Thanks a lot for your reply.