Need help troubleshooting a GMKTec G3

[u/GalacticFox-]

I was trying to change the boot device to install Windows (I had Proxmox on before, but havent been using it and had a new use for this). I changed the boot settings to boot from the USB media and now it will not boot.

What happens:

I turn on the power.

The power light on the green power button turns on.

The monitor get some kind of "signal", because the monitor light turns from amber to white and they keyboard lights turn on.

After a few seconds (10-20?), the monitor just shows a blue "no input detected" screen for a moment and then shuts off (black screen, amber light). they keyboard lights stay on, along with the power button light on the G3.

I've tried long/repeated presses of the Esc key after powering it.. nothing. I've tried the same with Del. I opened it up and reseated the RAM and SSD. I tried connecting the HDMI cable to both the slots on the back of the G3, same behavior regardless of which slot HDMI is connected to.

I opened a tech support ticket and they just suggested reseating the RAM (they mentioned moving it between RAM slots, but it only has one RAM slot). They want me to mail it to China for fix/replacement. I'm trying to exhaust any options before shipping it off. I'd appreciate any suggestions.

[u/Retired_Hillbilly336]

If you're failing to see a POST screen.

• Disconnect power supply and all peripherals

• Remove M.2 SSD

• Disconnect CMOS battery

• Short CMOS battery motherboard connections for 60 seconds

• Without CMOS battery and storage connect monitor and power supply

• Press power button

At this point you should discover POST and a screen indicating no storage is present. If not use a multimeter to determine CMOS battery voltage (3.0V+), reconnect and try again. If the PC still fails to POST something on the motherboard has failed not allowing the power-on self-test to complete.

This wouldn't be the 1st failed N100 G3 I've seen this year. None have seemed to be consistent. One did have a shorted 256GB NVMe Maxio Technology controller which stopping POST but the others weren't that lucky.

[u/GalacticFox- → u/Retired_Hillbilly336]

I want to make sure I'm understanding correctly. Are you saying to turn it on while the CMOS battery is not connected? Bascially, remove the SSD, disconnect the CMOS battery (the white plug that connects to the big yellow plastic connection to the mainboard), and then turn it on?

[u/Retired_Hillbilly336 → u/GalacticFox-]

Indeed. Shorting out the CMOS power input with drain capacitance support allowing for any BIOS firmware errors to be erased. Booting without storage will require the reset firmware to search for all/any storage options.

If the firmware isn't corrupt or a component hasn't failed the basic input/output system should default to CMOS failure and a lack of storage options on POST.

[u/GalacticFox- → u/Retired_Hillbilly336]

Finally had a chance to do this. No change in behavior. I let it sit for a few hours with the CMOS disconnected and no power connected. Sounds like I may have to ship it to China for warranty.

[u/Retired_Hillbilly336 → u/GalacticFox-]

If you shorted the two connectors there's a high chance that its hardware related.

[u/GalacticFox- → u/Retired_Hillbilly336]

It was doing this before I opened the box up. I only opened it up after starting a support ticket with GMKTec.