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IEGD iHDMI not found after only VGA


Using IEGD I made a driver for a GM45 motherboard.

The board is using the CRT and iHDMI-C ports with VGA on the CRT and a DVI-D on the iHDMI-C.

I configured it for clone mode. The CRT is a clone of the iHDMI-C

The driver works fine unless the computer is booted and run without the iHDMI monitor and a CRT (VGA) monitor is connected.

After that, the iHDMI monitor will never be detected again.

Any help would be appreciated.

My goal by the way is that if only a VGA monitor is connected on the CRT port that the driver reads EDID and sets the monitor to native resolution. If only a DVI monitor is connected on the iHDMI port the monitor will use by default the native resolution. And if both are present the VGA/CRT will clone the DVI/iHDMI-C.

Additional note: I can get this all to work great if I install the driver with both a DVI and VGA monitor connected. Then reboot with both still connected. Then I enable the Windows Embedded Write Filter. The driver will then work exactly as I like it to. As soon as I turn off the write filter and boot with only the VGA monitor connected the DVI monitor will then never work again. If if it is the only one connected.

Thanks for reading and hopefully providing some help.

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I created a new installer that contained three configuarations.

No Default was selected.

iHDMI-C Only

iHDMI-C and CRT with CRT a clone of the iHDMI-C

and CRT Only

If I install the driver and then boot with the iHDMI-C (DVI Monitor) Connected and the CRT (VGA Monitor Connected) the clone mode works with no problem. Also the single DVI: UNTIL I boot with only the VGA Connected. After that the only thing that works is the VGA.

Even if I disconnect the VGA and reboot with only DVI I get no signal

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