Headless boot issue with ASRock H81 PRO BTC Rev2.0

[zigun]

Yesterday, got the problem with booting of headless rig based on ASRock H81 PRO BTC rev2.0 MB and 3 GPU (2 on risers, one in 16x PCIE), before it works fine around one month.
When I boot it up all fans working but it not booting (nothing on monitor if attach), but everything fine when monitor stay attached when press boot btn.
Also, it boot up headless when risers unplugged from MB just with one in 16xPCIE.

Troubleshooting which already done: mix cards risers in other slots, re-install drivers, clear CMOS of MB BIOS, unplug/plug all power connectors

Google and search in forum didn't help, just find that people has the same issue and only one solution is use monitor for boot or headless HDMI plug.

My last actions before problem occur was changing setting in wattool (fan setting and memory voltage and freq.)

Welcome with any suggestions, will be appreciated it

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[Greedful]

In bios, did you try to boot on board gpu and not on pci gpu?

[zigun]

In bios, did you try to boot on board gpu and not on pci gpu?

Yep, and it boots but GPU-z shows mess with GPUs (wrong info, nothig about memory/gpu clocks, voltage)

[Greedful]

In bios, did you try to boot on board gpu and not on pci gpu?

Yep, and it boots but GPU-z shows mess with GPUs (wrong info, nothig about memory/gpu clocks, voltage)

Did you connect a gpu with hdmi cable?

[zigun]

In bios, did you try to boot on board gpu and not on pci gpu?

Yep, and it boots but GPU-z shows mess with GPUs (wrong info, nothig about memory/gpu clocks, voltage)

Did you connect a gpu with hdmi cable?

Yes, HDMI to TV