Motherboard shuts off immediately after being turned on. Expert help needed.

[erosionexplosion]

Blabbering exposition:
I have been using a $120 US Chinese "Huanan X79 Deluxe" Motherboard for about 2 months now with 16GB DDR3 ECC RAM and a Xeon E5-1650 v2, with no issues whatsoever.
I purchased it from Aliexpress, with no hassle at all. However, I am outside of the Buyer Protection Guarantee so I have to either, 1: Attempt to converse with Chinese-only customer support, or 2: Fix the thing myself.

The motherboard fully supports AMD Crossfire, and I can confirm this myself with personal testing. I used 2 Gigabyte Aorus RX 580 8GB cards.
After some testing with single and multi-gpu benchmarking, I decided to put the second graphics card back into the system again...

ISSUE:
Now, the motherboard won't POST at all, heck, it barely even turns on for one second, glaring code "FF," then turns off immediately. I have some spare, known working CPUs, GPUs, RAM, and PSUs. No matter what I put into the board, it never wants to turn on.

My guess is that when inserting the second graphics card, some freak accident occurred where I... damaged a trace? But the instant shut-down seems more like some kind of Over-current protection. I'm fairly well-versed in PC hardware, and am quite stuck. I fear that I need some form of PCB replacement or repair.

 

[Nerdy Nerd]

So a couple of things, I am wondering if your second card works in a different system, maybe you damaged the second card somehow and that is preventing the system to boot, rare but possible. Secondly, not to insult you or anything but there is thermal paste there right? Cause no thermal paste would probably make the system shutdown extremely fast. Third, try breadboarding the system to rule out shorting out. Forth, try taking out the ram sticks and see if you get a beep code for now ram so you can see if it indeed in most likely the motherboard. In this case, I think the motherboard is bad but make sure you check by replacing the main parts with known good ones that you said you had, so cpu and psu.

 

[erosionexplosion]

So a couple of things, I am wondering if your second card works in a different system, maybe you damaged the second card somehow and that is preventing the system to boot, rare but possible. Secondly, not to insult you or anything but there is thermal paste there right? Cause no thermal paste would probably make the system shutdown extremely fast. Third, try breadboarding the system to rule out shorting out. Forth, try taking out the ram sticks and see if you get a beep code for now ram so you can see if it indeed in most likely the motherboard. In this case, I think the motherboard is bad but make sure you check by replacing the main parts with known good ones that you said you had, so cpu and psu.

Yes, I breadboarded the PC in question. I have a second PC with the same spare mobo, CPU, and RAM. I can confirm that my problematic PC's CPU, RAM, Graphics card, and power supply are functional.
The heatsink and fan are secured down tightly on my CPU, with Arctic MX-4 clearly squished across the CPU.
When taking out the RAM, I still get the super quick "FF," followed by shutdown. Even taking out the CPU entirely yields the "FF, power off." After powering off, the mobo attempts to turn itself back on again, then shuts off repeatedly.
Thanks for your input.

 

[Tumeden]

This guide will aid you in troubleshooting the FF, --, and 88 POST codes:

1) Power Issues

-Improper Voltage Settings
Verify that the power supply is set to use the 110v standard instead of 220v. There is a switch on the back of most power supplies that will regulate this voltage. 110v is used in the United States, Canada, and most other North American countries. 220v is used in most European countries.

-8 pin and 24 pin connections
Verify that the 8 pin and 24 pin power connections are connected to the motherboard and seated correctly. Reseat the 8 pin power connection and make sure that no adapters, extension cables, or other intermediates are being used between the power supply and the motherboard.

-Uninterruptable Power Supplies (UPS)
If an uninterruptable power supply is being used verify that the UPS is rated to sustain the wattage and amperage for the power supply being used in the computer. Also try plugging the machine directly into the wall if a UPS is being used. This will rule out any issues pertaining to a UPS.

-Faulty Power Supply
If the previous steps do not resolve the issue it is recommended to try a different power supply with the machine to rule out any power supply issues.


2) Grounding / Shorting Issues

-Motherboard Stand-offs
Ensure that standoffs are being used between the motherboard and the case, and the motherboard is not being screwed directly into the motherboard. Make sure that there is one standoff for each hole in the motherboard, and there are no additional standoffs making contact with the motherboard.

-Aftermarket Party CPU Coolers
If using an aftermarket CPU cooler that screws through the motherboard try unscrewing the CPU cooler and placing it on top of the CPU without screwing it down. If the screws are screwed too tight it can cause a shorting issue with the board that will cause it not to POST. Please note that this is for testing purposes only. Do not run the machine under normal use without properly attaching the CPU cooler.

-Ground Fault
Remove the motherboard from the case and place it on a non conductive surface (wood, cardboard, etc.). With only power connections, CPU, and CPU fan attached try powering on the motherboard. Please note that the machine will POST to an F6 POST code if board is POSTing. The F6 POST code will signify that there is no memory installed. If you receive this error you can continue to rebuild the machine as normal.


3) CPU Problems


-CPU Detection
Verify that the CPU is properly seated in the CPU socket and that there are no bend pins on the motherboard. If all of the pins appear to be intact try reseating the CPU in the socket and see if the motherboard will POST.

-CPU Fan
Make sure that the CPU fan is correctly attached to the processor and the fan header is plugged in to the correct header on the motherboard. If the CPU fan is not attached to the correct header on the board, or not attached at all, the motherboard may not POST correctly.

-CPU Dip Switch (790i FTW Digital PWM only)

The 790i FTW Digital PWM Motherboard (132-YW-E180-A1) has a tiny dip switch near the CPU socket towards the top of the motherboard. This switch toggles different power modes for your CPU. Leave the switch to the "1" position for Core 2 processors and above (Core 2 Duo, Core 2 Quad, etc.). For Pentium 4 or older processors flip the switch to the "ON" position. If this switch is set to the incorrect setting the motherboard will not POST and result in the motherboard going straight to the "FF" POST code without cycling through other POST codes. If the board doesn’t post and goes to FF automatically turn the machine off, flip the switch from the 1 to the ON position, and see if it posts.

-Faulty CPU
If the above steps do not resolve the issue then it is recommended to try a different CPU in the motherboard to rule out any potential CPU issues.

4) BIOS Issues

-Improperly Seated BIOS Chip
Try pressing down on the BIOS chip of your motherboard to verify that the BIOS chip is correctly seated in the motherboard. The BIOS chip is generally located near the CMOS battery of your motherboard. Give the BIOS chip a little pressure to see if it will click into place.

-CMOS Clear
Try clearing the CMOS of the motherboard by removing the CMOS battery from the motherboard for a period of time. You can also clear the CMOS by moving the clear CMOS jumper from pins 2 and 3 to pins 1 and 2 for about 30 seconds. After 30 seconds move the clear CMOS jumper back to pins 2 and 3.

 

[erosionexplosion]

This guide will aid you in troubleshooting the FF, --, and 88 POST codes:

1) Power Issues

-Improper Voltage Settings
Verify that the power supply is set to use the 110v standard instead of 220v. There is a switch on the back of most power supplies that will regulate this voltage. 110v is used in the United States, Canada, and most other North American countries. 220v is used in most European countries.

-8 pin and 24 pin connections
Verify that the 8 pin and 24 pin power connections are connected to the motherboard and seated correctly. Reseat the 8 pin power connection and make sure that no adapters, extension cables, or other intermediates are being used between the power supply and the motherboard.

-Uninterruptable Power Supplies (UPS)
If an uninterruptable power supply is being used verify that the UPS is rated to sustain the wattage and amperage for the power supply being used in the computer. Also try plugging the machine directly into the wall if a UPS is being used. This will rule out any issues pertaining to a UPS.

-Faulty Power Supply
If the previous steps do not resolve the issue it is recommended to try a different power supply with the machine to rule out any power supply issues.


2) Grounding / Shorting Issues

-Motherboard Stand-offs
Ensure that standoffs are being used between the motherboard and the case, and the motherboard is not being screwed directly into the motherboard. Make sure that there is one standoff for each hole in the motherboard, and there are no additional standoffs making contact with the motherboard.

-Aftermarket Party CPU Coolers
If using an aftermarket CPU cooler that screws through the motherboard try unscrewing the CPU cooler and placing it on top of the CPU without screwing it down. If the screws are screwed too tight it can cause a shorting issue with the board that will cause it not to POST. Please note that this is for testing purposes only. Do not run the machine under normal use without properly attaching the CPU cooler.

-Ground Fault
Remove the motherboard from the case and place it on a non conductive surface (wood, cardboard, etc.). With only power connections, CPU, and CPU fan attached try powering on the motherboard. Please note that the machine will POST to an F6 POST code if board is POSTing. The F6 POST code will signify that there is no memory installed. If you receive this error you can continue to rebuild the machine as normal.


3) CPU Problems


-CPU Detection
Verify that the CPU is properly seated in the CPU socket and that there are no bend pins on the motherboard. If all of the pins appear to be intact try reseating the CPU in the socket and see if the motherboard will POST.

-CPU Fan
Make sure that the CPU fan is correctly attached to the processor and the fan header is plugged in to the correct header on the motherboard. If the CPU fan is not attached to the correct header on the board, or not attached at all, the motherboard may not POST correctly.

-CPU Dip Switch (790i FTW Digital PWM only)

The 790i FTW Digital PWM Motherboard (132-YW-E180-A1) has a tiny dip switch near the CPU socket towards the top of the motherboard. This switch toggles different power modes for your CPU. Leave the switch to the "1" position for Core 2 processors and above (Core 2 Duo, Core 2 Quad, etc.). For Pentium 4 or older processors flip the switch to the "ON" position. If this switch is set to the incorrect setting the motherboard will not POST and result in the motherboard going straight to the "FF" POST code without cycling through other POST codes. If the board doesn’t post and goes to FF automatically turn the machine off, flip the switch from the 1 to the ON position, and see if it posts.

-Faulty CPU
If the above steps do not resolve the issue then it is recommended to try a different CPU in the motherboard to rule out any potential CPU issues.

4) BIOS Issues

-Improperly Seated BIOS Chip
Try pressing down on the BIOS chip of your motherboard to verify that the BIOS chip is correctly seated in the motherboard. The BIOS chip is generally located near the CMOS battery of your motherboard. Give the BIOS chip a little pressure to see if it will click into place.

-CMOS Clear
Try clearing the CMOS of the motherboard by removing the CMOS battery from the motherboard for a period of time. You can also clear the CMOS by moving the clear CMOS jumper from pins 2 and 3 to pins 1 and 2 for about 30 seconds. After 30 seconds move the clear CMOS jumper back to pins 2 and 3.

Thank you for attempting to help. I have tried all of these options, and none have been successful.

I will search my community for motherboard repair services.

Hopefully I only just blew a capacitor, and didn't damage a motherboard trace.