vga hang on post, ok after 'reset', with kernel 6.7.9 + intel i915 + wayland drm . bug?

[pgnd]

hi,

i run release

	Fedora 39
	KDE 5x / wayland drm

with kernel

	6.7.9-200.fc39.x86_64 x86_64

on

	ASUS PRIME X570-PRO motherboard, BIOS v5003
	AMD Ryzen 7 3700X 8-Core Processor

i've a

	DELL U2722D monitor
		BIOS vMT3102
		connector is card1-HDMI-A-2
		DDC/CI is enabled

i've installed

	Intel Arc A380

from clean BIOS install, it boots fine -- gfxcard's identified, no apparent errors in system boot, & all appears to function on desktop.

on system reboot -- via e.g., `shutdown -r now` -- the system reboots, with no logged errors.
the Monitor displays "No HDMI signal detected", and drops into "Standby" mode.

on BIOS post, the system hangs
the white q-led (vga) is on; boot proceeds no further.

simply hitting 'reset' button re-posts, and the system boots. no hang, no errors.

this is 100% reproducible.

i've done the usual dance of,

	replace the video card
	swap video slots
	reinstall both current & previous BIOS versions
	reset CMOS
	remove/reseat all cards, RAM

nothing, so far, fixes the hang on post, with immediate success after 'reset' behavior
	
without any solid proof yet, i suspect power management (DPMS?) is involved ...

here's the current dump of (lots) system info, etc.

	https://gist.github.com/pgnd/9209983f5ca478b06bd5055188567f19

what further diagnostics/fixes are helpful/relevant here?

if this isn't the right forum, kindly point?

thx o/