What @Ashpool suggested seems to have worked for me. In case anyone is interested, here's what I did...

First, with the RP up and running and the TV screen displaying correctly, I queried for the HDMI mode used:

$ tvservice -s state 0xa [HDMI CEA (16) RGB lim 16:9], 1920x1080 @ 60.00Hz, progressive

From this and the RetroPie documentation on HDMI Mode I learned that in /boot/config.txt I had to set

hdmi_group=1

(for CEA) and

hdmi_mode=16

(for 1080p at 60Hz and 16:9). I also had to add

hdmi_force_hotplug=1

After rebooting the RP, the issue was resolved.

Thanks again, @Ashpool!

@mitu - Thank you! I wasn't. I am now and the xrandr commands have worked.

framebuffer_priority=7

was the only option I needed in config.txt to get emulation station to work from hdmi 1.

(I needed to use this as the fat micro hdmi adapter I was using pressed against the usb-c power connector)

These are the only options I have set in config.txt (audio and video on second hdmi port 1 work fine in emulation station)

framebuffer_priority=7 # OVERCLOCK SETTINGS arm_freq=1800 # CPU Frequency gpu_freq=600 # GPU Frequency over_voltage=2 # Electric power sent to CPU / GPU (4 = 1.3V) dtparam=audio=on # Enable DRM VC4 V3D driver on top of the dispmanx display stack dtoverlay=vc4-fkms-v3d max_framebuffers=2

@mitu Here's the text that came out after the commands:

AP///////wBMLe4NAA4AAQEbAQOAeUR4CiOtpFRNmSYPR0q974BxT4HAgQCBgJUAqcCzAAEBBHQA MPJwWoCwWIoAUB10AAAeAjqAGHE4LUBYLEUAUB10AAAeAAAA/QAYSw9RHgAKICAgICAgAAAA/ABT QU1TVU5HCiAgICAgAToCA0/wU18QHwQTBRQgISJdXmJjZAcWAxIsCQcHFQdQPQTAVwcAgwEAAOIA D+MFAwFuAwwAQAC4PCAAgAECAwTjBg0B5Q5gYWVm5QGLhJABAR2A0HIcFiAQLCWAUB10AACeZiFW qlEAHjBGjzMAUB10AAAeAAAAAAAAAAAAAAAArQ==

Additionally, after hours of messing with this, when I plugged it in today it was magically working. I had just rebuilt the box after an issue with SSD corruption. I'm still willing to pull data/test to help anyone else who has come across this issue. I also plan on rebooting a few times to see if this is a fluke.

@jamrom2 Definitely. When the cable company upgraded to the 'slide' version, I played with it endlessly.slide box

@mitu said in Tried to prioritize HDMI output over LCD now my LCD doesn't work at all:

@ns27 Revert the change you've done and see if it fixes it.

ok ill try that

@Xystus777 Normally this is done by runcommand when launching a game, by running

setterm --blank poke

Are you not using runcommand to start your game ?

@ikarampa Is is a post that's 13 months old, opened for PPSSPP on a Raspberry Pi. You might have better results posting on the LibreElec forums to ask for advice.

@gengar103 said in Pi 3 - no HDMI display:

What can be done to get this LCD panel, which worked fine under 3.8.1, to work under 4.3?

Try editing /boot/config.txt and add this hdmi_force_hotplug=1

@xsportseeker well i guess i read that all for nothing!! :) yeah im glad i read your second post because i was about to point you to that file. Glad you got it working. If you are interested in making .sh files to have all dos games show up in the gamelist or any other configuring help in dosbox feel free to ask.