My version of rg35xxh works well without any manipulations.
Try to use another dtb with over LCD panel timing.
I’m unsure what over LCD panel timing is or where I could get a dtb with that enabled. I tried with just the ROCKNIX dtb and the base kernel (ROCKNIX works perfectly for me and I’ve had success with its prebuilt dtb & kernel when frankensteining my own NixOS boot) and had the same issue - the power LED turns off after a second or two with nothing displayed on screen. I also tried the rev6 panel dtb but that didn’t work either (I don’t have a rev6 panel though)
Where should I go from here?
Maybe it’s something with the axp pmic (rsb or i2c) mode. Try to completely reboot your device by unplugging the battery - this will reset the pmic mode in i2c. If that doesn’t work, then you need to plug in the UART to know for sure what’s going on
I just opened the device and unplugged the battery, it didn’t work. Green power light turns on, turns off a few seconds after. Tried again with a fresh flash of your retroplasma build using rpi flasher to my 32gb card. Unfortunately I don’t have a UART converter so I cannot see exactly what’s going on. I did see on the internal board that my device is a V4 revision model. I’m convinced that its something to do with the provided dtb and kernel, since I can get something displayed if i just drop in the rocknix dtb + kernel in place of the defaults. Maybe I have to try with a fresh SD card?
It looks weird. If possible, you can try another microsd. Indeed, I have no idea what else the problem could be
Follow up: I just tried flashing with brand new micro SD card and it worked. Will be looking into why the other cards are failing. Thanks for the help!