Boots from USB but no HDMI output

Yes, we need to get your display issue understood. You do see the Raspberry Pi boot screen? Or you don't see anything ever? Snap a picture or video if you want and share it here. You don't happen to have a different CM4 you can test with do you? Unfortunately, seeing damage on the CM4 board pins is really challenging. Sometimes they even pop off and you can't tell.

I don't get any display, not even the rpi boot screen. That's what convinces me it's a hardware issue with the CM4, HDMI cable or monitor... and unfortunately the CM4 is the most likely culprit. Just bought a second one, I'll post back with results.

It is very unlikely the both HDMI ports are bad. They are completely separate from each other and both run directly to the CM4. Even if there were slight issues with the traces running to the ports, you would still get mixed up garbage on your screen rather than nothing at all. We look forward to hearing your restuls. I am also glad that they are in good supply again. What a nightmare that was.

I just downloaded and booted into live mode the version of OMV OS we have on our site and it worked just fine. Boots to the Interceptor Login prompt. You can, as I noted, install to the USB stick itself and run everything from there. Please let us know how it goes.

Cool. Only problem is, I can't use the axzez installer without a screen.

the IO board arrived today and I successfully flashed the latest bootloader. BUT even on the IO board I have no HDMI output. I would expect at least the rpi diagnostic screen (right?). So that suggests hardware: the HDMI cable, the monitor, or the CM4 itself.

• I'm confident in the cable and monitor because they're my daily driver for my laptop. It's a samsung widescreen though - maybe the RPI doesn't like the edid? Or is trying an incompatible resolution?

• I have a really hard time imagining a scenario where the CM4 is damaged in a way that only impacts the HDMI outputs. There's no visible damage to the pins. On the other hand, `lspci` comes up empty.

How can I prove the hypothesis that it's the CM4 itself (or its connectors)? What should my lspci (or dmesg) output look like? Reading dmesg it all seems normal to me - it finds all 4 cores, the ethernet device, etc etc . But I don't have a baseline to compare.

No HDMI on the IO board is certainly telling. A second CM4, as you've ordered, should tell us what we need to know. I personally cannot imagine if your HDMI cable and monitor work elsewhere, that they'll not work here, but I'll do some digging on that. I've used wide screen monitors (DELL) with our Interceptor systems. Since you know it boots, I guess we don't need to go the DMM route and test your PSU output. (just thinking out loud). You don't happen to have another monitor to test with do you? Maybe a friend has one you can borrow?