Hey everyone!
I flashed a BIOS via FLASHBACK, and this is what happened: the board boots up, then stops for 2 seconds at 63, then stops at 65 about 4 seconds long, then 4 seconds at 6F, then 7F for 4 seconds as well -- then proceeds to boot, but no video output is detected (= d6). - you can check what the POST codes mean
Then according to the LED indicator, I'm in the BIOS (= A6) - but obviously no video output. It doesn't matter from which BIOS chip I boot, the issue is persistent though I only flashed the BIOS on 1 chip -- and of course, FLASHBACK doesn't solve the issue, no matter what BIOS I flash.
The board sometimes instead of entering the BIOS (theoretically --> "A6") gets past the POST process and tries to enter the OS -- this "theory" is supported by the LED indicator which displays the CPU temps after the POST process by default. After about 10 seconds, the CATERR LED lights up. It's also important to note that the keyboard receives power during the POST process but after the board attempts to enter the OS, it does not.
It isn't the GPU (it was working before and it is working in another computer). I already left the battery out for a whole night, but nothing. Also rebuilt the computer, and apart the CPU (which I cannot test since I don't have another compatible motherboard) every component is functional.
What should I do?

valakiakiszeretiafocit
It doesn't matter from which BIOS chip I boot, the issue is persistent though I only flashed the BIOS on 1 chip

I tried that already as you can see from my previous message - for some reason the issue remains

Sajin
Did you try the card in another pci-e slot? Did you try hdmi and dp outputs on the video card?

Yeah - attempted both already -- same outcome

Disconnect every single USB item from the motherboard. What is the behavior when attempting to boot?

Any other ideas? - I've ordered an SPI programmer but to be honest I don't think it will fix the issue as I've only flashed the BIOS on 1 chip, yet none of them works. Like it'd be hilarious if after a BIOS flash the board can't be used anymore

Unfortunately it isn't the CMOS battery as the board boots (unlike by Luumi) with and without the battery (+ I checked the voltage with a multimeter).

Any ideas what is the `SP1` connector used for? I didn't find any documentations related

I've received the SPI programmer, but I can't attach the clip properly. The chip is not detected when attached to the BIOS chip, nor when to the SPI1 connector

Jaaco

valakiakiszeretiafocit
I've received the SPI programmer, but I can't attach the clip properly. The chip is not detected when attached to the BIOS chip, nor when to the SPI1 connector

heres a detailed post that should help you: 
 
i'm planning to try myself on the Z490 Dark this week and will update you.

I've already read that blog but unfortunately couldn't get it work. If you can get it to work, I'd highly appreciate your experience - thank you, really!! Happy New Year! :)

I'm still planning on this - I forgot my brother has my SPI programmer for a coreboot project.
I have my jumper cables and adapter ready but he has my green CH341a (and clip).
Sorry to extend this , but I need a little more time.

My jumper ribbon cables are too wide to fit together on the SPI1 connector.
 
I'm sorry to say it appears to requires tape with probes and this ends my attempt. I wanted to try but I can't spend the time needed for probes.
 
SPI FLASH chip documentation: https://www.gayocen.cn/zyGD/806.html
 
I'm familiar with coreboot's flashrom:
git clone https://review.coreboot.org/flashrom.git && cd flashrom
make
sudo ./flashrom -p ch341a_spi -w /home/user/backup.bin
 
really wish you luck. takecare.

I wrote back a few weeks ago but my post disappeared.
 
my jumper cables do not fit the pins .. so this requires probes (with tape to hold in place). im sorry to say this ends my attempt.

valakiakiszeretiafocit
Any idea how to contact EVGA support (without being able to register the product on their site)?

Please contact EVGA by email at  Support@EVGA.com
 
Include the product part# & the serial #
 
you can reference your thread https://forums.evga.com/FindPost/3615446