On board HDMI does not display POST on cold boot.

[gordy7]

New build out-of-the-box Prime Z690-A does not display POST startup page on cold boot using on board HDMI.
POST completes in the background and boots up Win 11 Pro without further problems.
POST correctly displays startup when using on board Displayport.
Same issue with Bios 0703, and 1601.
Bios is reset to optimal defaults.

This is not an ideal experience that new builders should face.

CPU i9-12900K, Ram Corsair DDR5 32GB, PSU Corsair RM650 650W.

This is a CAD computer and not an overclocked gaming computer.
Windows 11 Pro successfully passes various benchmarks and runs all my CAD applications.
I have not seen this sort of Bios startup failure in my other computers.

[hdtvnut]

I have the same problem with a Z690 Hero and w10. My monitor is a 4K Acer; if I hook a 2K to HDMI instead, it shows and allows me into bios.

[Dunkelstar]

I also had problems with the integrated Intel graphics on a Z690-I build. WIndows failed to load every time I tried using the integrated graphics along with an NVMe M2; worked fine with a SATA M2 installed. Once I installed my dedicated graphics care, the system installed Win11 on the NVMe M2 and runs fine. Not sure what's going on, but it seems that the PCIe bus has a conflict when running a NVMe M2 and the integrated CPU graphics at the same time. The same issue was present on two Z690-I MBs, so unless both boards had the exact same chipset failure, it seems like a systemic problem. Not good . . .

[gordy7]

I have the same problem with a Z690 Hero and w10. My monitor is a 4K Acer; if I hook a 2K to HDMI instead, it shows and allows me into bios.

On cold start I can get into the BIOS if I press the DEL key - even though there is no HDMI POST display.

Windows 11 Pro boots and runs fine at 4k HDMI with a 4k Philips BDM3275 monitor (HDMI 2.0)

[gordy7]

Tested today... Cold boot on board HDMI correctly displays the POST startup screen when using a 2k monitor.
2k monitor has HDMI 1.4
4k monitor has HDMI 2.0.

[gordy7]

Best my supplier and Asus can offer is a motherboard return for repair or replacement.
As the lack of POST startup display when using HDMI with a 4k monitor is a fairly minor fault I have decided to keep the motherboard.
Motherboard works fine with Windows 11 Pro and HDMI at 4k.

Edit:
Motherboard was bought in mid June 2022 and the system build completed at the end of June when the RAM arrived.
Manufacturing date of motherboard Nov 2021.
Asus were notified of the HDMI 4k no startup POST display within a week of the build but there has been a lot of email exchanges.

[hdtvnut]

Thanks for that info. Occasionally I do get a post screen with the 4K, but I can't figure out a way to do it reliably.