ROG Z790-F black screen, no logo, no POST after unplug ac power.

[anym0re94]

Hi, my z790-f show black screen with q-led (boot) light up after unplug ac power or switch off psu (shutdown gracefully before unplug). I tried to change from dp to hdmi but screen still black (my screen is working properly with normal signal input but the image just being all black), and I tried to reinstall my m.2 still no fix (m.2 is no problem). 

The only fix I know is reset cmos. I dont know why but after cmos reset everything work just fine, my pc can boot to os everything is normal.

Is there any better solution? Is my mobo normal?

Thanks

[Jiaszzz_ROG]

Hello, @anym0re94 

Resetting the BIOS settings will initiate a self-check during startup with the default parameters and settings.
This is one of the troubleshooting methods for resolving boot issues.
May I inquire if the issue of being unable to boot has been resolved after clearing the CMOS?
Before encountering the boot issue, were there any adjustments made to the BIOS settings?
If the problem persists or if you encounter the inability to boot or a black screen again, please refer to the following FAQs for troubleshooting:
How to clear CMOS?
[Motherboard] ASUS motherboard troubleshooting via Q-LED indicators
[Motherboard] Troubleshooting - No Power/No Boot/No Display

Thank you.

[anym0re94]

thanks for your reply.

if the issue of being unable to boot has been resolved after clearing the CMOS?
yes, everything work just fine after clearing the cmos. post / logo came up then boot to os.

Before encountering the boot issue, were there any adjustments made to the BIOS settings?
no, not at all. even if the bios is on default settings or after clear cmos, if i switch the psu off or unplug ac cord, next time i switch on my pc, my screen will be black. then, like i told you, after clear cmos everything seem to work properly (but man, i dont want to config bios everytime i unplug 2 move my pc 😢)

If the problem persists...
How to clear CMOS? : check
troubleshooting via Q-LED indicators : check. try reinstall m.2. this problem occurs even no m2 or no ssd installed at all (so i dont think it's boot media problem. and i'm 100% sure that my m.2 work perfectly)
[Motherboard] Troubleshooting - No Power/No Boot/No Display : check. tried on 2 screen, tried hdmi / dp with 1200w psu.

[Jiaszzz_ROG]

Hello, @anym0re94 

According to your description, it seems that you need to clear CMOS every time to boot successfully, otherwise, cold booting is not possible.
Could you please confirm if there are any Q-LED indicator lights on or any Q-codes displayed when the system fails to boot?
We suggest you refer to [Motherboard] Troubleshooting - No Power/No Boot/No Display and test with minimal components to isolate the possible cause.
Meanwhile, if you haven't updated to the latest version 1801 released on December 22, 2023, please consider updating and clearing CMOS before rechecking again.

Thank you.

[anym0re94]

I ran some test with minimal component (only cpu and ram installed NO m.2 or any ssd) the problem still occur.
Yes q-led (boot) light up and the system got stuck on black screen.
And yes my bios is 1801 and yes i tried roll back to some previous version the problem still there.

[Keith-Yami]

Have u found the solution?

I have the same issue. I even asked 6 months ago and again last month. Same as u , press cmos jumper is a work around. That's what i found out. There has no solution.

My board is Z690F gaming wifi.

Please tell me if you've found a solution. I feel sick when i asked and ppl keep answered as reset cmos and check every part of hardware to make sure no faulty. I checked all, and i told them as a long post. But well, they don't bother to read. They just answered as "check bios, load default bios, reset cmos, reseat ram, gpu, reinstall software, windows, etc" even i posted a long post about "how frustrated after i did all those stuff and still have no bios on cold boot"

Btw, is that you also need to re-enable PTT when settings up bios again to make sure to able to login windows?

[anym0re94]

no, not yet. the problem still occur everytime i cut the power. now i think it's a mobo defect, but other than black screen thing, everything works just fine. so i think i have to live with it, or wait for next bios version.

and no i dont have to re-enable ptt, my mobo enabled it by default, i guess. i mean i never ever touch that setting before.

and if you found the solution, please kindly share.

thanks.

[Silent_Scone]

Might seem like an obvious question, but have you tried making sure the monitor is switched on before powering up the system to see if that makes any difference?

[anym0re94]

sure thing my both monitors are switched on. even tried unplug dp cable to another monitor the screen still black (the screen signal is normal, but the image just went all black). and i got the same result with hdmi port even dp, hdmi on rtx vga.

[Keith-Yami]

my mobo did POST. it passed until boot and hanged at green boot led.

CPU - red led, passed
RAM - orange led, passed
VGA - white led, passed.
BOOT - green led, hanged.

no bios splash screen until i press cmos jumper. but if i let it as default settings. when i get into windows 11. it said some sort of re-create PIN. so basically TPM down. then i need to re-enable PTT to make sure TPM work fine.

i tried all stuff. from cmos, reseat, reset cmos..

i even doubt if it's cable issue. like displayport from monitor is 1.2 and vga output 1.4 .
first, i buy a new cable as 1.4. since those cable will compatible with earlier 1.2 version. but it's not working.
then, i even buy a new asus monitor with hdmi 2 to make sure it fit with hdmi output from vga and igpu.

but geez, it won't work. maybe i have a good solution as buy a new asus mainboard, lmao. a new pc to solve the issue that they ignored to help or not know how to. 

p/s: aboout buying whole new pc. it's just a joke, not mock. i feel it's fun to say. so yah, just say it.

but before buying a whole new pc, i think i should try a new vga for the correct displayport & hdmi port output i guess.
and i realized, igpu has a latest driver which support the latest port stuff. and my new asus monitor also supported it. but it won't work. so basically, a new vga won't give a ****** on it.

then i tried another solution as sfc /scannow. to find if there's windows issue.
and yes, it showed some errors and fixed. but after that, nope, still same.

then i doubt about windows efi problem.

so, bootrec /fixmbr stuff. but surprisingly, when bootrec /scanos from X. it doesn't see any active disk.
and i digged deeper into it. go into efi partition. it found active OS.
then after that. same issue. passed some POST and hanged at boot led.

then i tried take off all hard disk to see if it can boot to bios. it should boot into bios without hard disk if it's normal. but no. still boot led.
if i plug off display cable and reboot. it will hanged as white led even if i plug it in again. if display monitor is in, vga led will be passed.

so i assume it's some bios issue. then flash bios.
yep, flashed and upgrade successfully. but after that. still need reset cmos.

so i doubt if it's something about boot entries on bios?? the shellx64.efi i guess. sorry not a pro, so i don't know what it is. but i hope it can be helped to solve it.

and fact i can't see any where to download that shellx64.efi to test if it can be fixed that issue.

i always doubt it's something happened at boot entries.

because if mainboard issue, it supposed to be completely not worked even if reset cmos.
and bios is fine, because the settings of time is still there. so it proved bios saved settings.

the only thing which i couldn't check yet, it's boot entries.

and yeah, i see so many ppl like us having a fun problem like this, if cut the power after shutdown gracefully. tmr = surely reset cmos via jumper. if we didn't cut the power, then it's fine. and pc works fine.

pc works fine which means hardware, software are abnormally fine