Computer is not powering down after shutdown command

[Grimvald]

Hi, I have a problem with the older hardware. The hardware in question is the following

CPU: AMD FX8320 with an LC Power CPU cooler + 2 Noctua fans for push-pull
Mobo: Gigabyte GA-990FXA-UD3 revision 4
RAM: 16GB Kingston fury (2X8) 1866mhz CL11
GPU: MSI RX470 Gaming 8GB
SSD: Sandisk 120GB boot drive
HDD: 2x Seagate Baracuda 1TB drives 7200 RPM
PSU: Silverstone 750W power supply 80+ silver
Case: NZXT Lena S

So the problem is the following. The computer is working normally, starts up normally, stressed the system and all the things are working. The only issue that it has it is not turning off. Sending shutdown command would send pc to turn off, and all the components will be off for 2 seconds and then would power up again as someone pressed the button. Checked with pulling out RAM and leaving only one memory stick and in a different slot.
Replaced graphics card with the MSI HD7850, still, the same. New PSU Seasonic am2 750w 80+ bronze, no change, replaced case with Zalman z9, same.
So in the end I suspect that is a motherboard but could be a CPU issue as I do not have another board or another CPU to test it out.
Does anybody know what could be the problem as the issue that the computer will not shut down, but working normally? This is not a software issue as when you hold the power button it will also go in a short turn-off state and power on again on both cases, so it is not a power switch as well as two different cases are in.
One notice is that the computer will shut down if it is cold (1-2 hours of power on time with light usage) any game or longer running would cause this to happen. Also cannot go to standby. As soon as it goes it would wake up from it.

Thank you

 

[Jetster]

Something is keeping it awake
Try disconnecting your mouse.
You can go into the advance power setting and disable stuff to not wake. I forget what its called. USB suspend settings disable
Also set your power button to off not sleep
Those boards have issues with sleep

 

[Grimvald]

It is off. ERP setting is on so nothing can wake PC once it is off. No standby power if the PC is off. The power button is set to off as well. In bios, it is set to after 4 seconds holding the button to turn off the PC.
Another point is yes, they have issues but I have the latest bios revision from Gigabyte support 4c that is not public so it was working ok before that.
Also, PSU supports that functionality to not keep the motherboard under less power than standard (USB has no power in of state for example).
I have also unplugged SDD and HDD to check if this is the issue, no luck as well.

 

[Chrispy_]

Yeah, what @JESTER said. Disable wake on USB in the BIOS, or work out what peripheral you have plugged in that's failing.

 

[biffzinker]

Something in Windows to try is disabling "Wake Timers" under Sleep for the active power plan. Is there a device on your network that could be telling the PC to wake up via the Ethernet connection (Wake on LAN?)

Yeah, what @JESTER said. Disable wake on USB in the BIOS, or work out what peripheral you have plugged in that's failing.

Could it be a Wake on LAN issue the OP is experiencing?

 

[protain]

Could it be a Wake on LAN issue the OP is experiencing?

WOL would only be happening if something was sending the magic packet to the device, more likely to be an over-sensitive sensor on a usb mouse (it's always been that for me in the past)

Might also be a setting (or bug) in BIOS... maybe worth updating to recent version and/or wiping the settings to default to see if that resolves it

 

[Chrispy_]

Could it be a Wake on LAN issue the OP is experiencing?

Not impossible but unlikely unless something else on his network is infected with Malware and trying to PXE boot devices. I'm assuming he hasn't intentionally set up something to wake network PCs based on this thread

I've encountered this random-wake issue a few times before and @protain is likely correct in that it's a failing USB device or port. Squirting compressed air at all the case's USB ports might cure the issue if there's something causing a short fallen into one of them....

 

[TheoneandonlyMrK]

Could be a faulty On switch, try swapping it off and use the reset button or a screwdriver, just to check.

 

[Grimvald]

Faulty on switch is not as described in the original post to eliminate that issue I have switched the case from NZXT Lena S to Zalman Z9 and the issue persists. All wake-up triggers are disabled in bios.
Wake up on power restoring off
Wake up on LAN, off
Wake up mouse off
wake up keyboard off
ErP/EuP is on
Bios reflashed and used in stock settings. And then activating XPM, SVM, fan setup, enabling ErP/EuP, and removing wake up events from bios.

Removed all USB devices except mouse and keyboard. There are 4 PC in the house, so I believe that if there was a malicious issue, other PCs would be affected as well.
If it is a failing USB port, what would be the solution for that? Simply not plugging anything into it or will it cause the issue constantly?
I will test for the USB issue. Just one thing, does this mean that the board is dying or just glitching?

Thanks

 

[Chrispy_]

You haven't unplugged the two USB devices that are most likely to be the culprit. It's usually been a faulty keyboard when I've seen it happen.

First step is to clean the ports (compressed air is good for this, just jam the straw in the back of the port and squirt) and make sure all the USB headers on the board are either plugged in all the way, or that none of the pins on the unused ones have become bent and are making contact.

If the port is damaged and shorting (at least on the case) you can just unplug the case header. If it's shorting on the rear IO panel you're out of luck but chances are good you'd see physical damage to the port which might be repairable with a pin, blade, or toothpick.

 

[Grimvald]

kIt looks like the issue was with the ErP/EuP. Once I have disabled it, it started working okay again. Also reladed bios to some voltage default values and no longer set CPU to 1.3V and RAM to 1.5, as for some reason on auto it was going down to 1.35V.

Thank you all for support

 

[RJARRRPCGP]

I had an issue with WOL before. That would cause my PC to randomly turn on.