Very bizarre boot issue - Raspberry Pi 3B v1.2 vs 3B+ v1 2

I've got an issue here I can't quite seem to get to the bottom of, I've been working on it for weeks. Here's what I'm working with: 5v 2.5a power supply, high quality. No undervoltage warnings in dmesg UPS Desktop variable voltage power supply (taken from a workstation) 8GB quality microSD card - passes checks | boots from other device 16 GB quality microSD card - passes checks | boots from other device 128 GB quality microSD card - passes checks | boots from other device All installations described below are using the official R-Pi Imager software (Windows) with latest updates Also tried flashing cards via Ubuntu All cards are being formatted using the official SD card association formatter for Windows (as described in the Boot issue sticky on the R-Pi forums) That said, I have an R-Pi 3B v1.2, and an R-Pi 3B+ v1 2 (no dot on the PCB silkscreen, assuming it is also a v1.2) The 3B is able to run everything I put on it. Raspberry OS, OctoPrint, Home Assistant, etc. The 3B+ will not boot from the stock Raspberry Pi OS 64 bit flashed onto the card via the official imager - just the seven green LED blinks (failure to locate boot kernel) The only thing the 3B+ will boot from is Octopi (the last version from the official R-Pi imager). I've tried everything in the boot-issue sticky (on the official site, on the reddit forums), reformatted card many times, also tried to manually replace the "boot8.img" kernel from the Github. The thing will only run Octoprint , and it works great - keyboard, monitor, webcam, ethernet, wifi - any idea what gives? Could this still be a hardware thing? I'm totally out of ideas! Since it's a 3B+ there's no EEPROM testing image to boot from, are there any other lightweight OS's that I can use to troubleshoot? Perhaps boot to Octoprint and then install some diagnostic utilities from there? I'll try anything! Thanks so much in advance 🙏

There are two options you could test: 1. Download the image from the web site and create the SD/USB from the downloaded image. And also verify the SHA on the downloaded image. 2. Boot from USB stick. This is not a scientific advice just a shoot in the dark.

thanks - bought new power supplies and new SD cards just in case

is it safe to believe that the R-Pi imager is pretty solid?

(also I can't seem to get the internal WiFi to work for either of them but apparently everyone has that issue and uses as wifi usb dongle)?

yeah brand new sandisk extreme sdcard + official rpi from image still wont boot

its so weird that the 3B will boot it and the 3B+ will boot octoprint it suggests that there is something wrong with the imager coming from rpi imager

so inspecting my board more closely, i see it does not have wifi/bluetooth hardware installed (at the top left there should be a metal plate with the raspberry logo covering the modem) i also can't get it to boot rasperian lite - i think this might be some kind of a one-off board, its from 2014 perhaps it is 32 bit only

yeah, confirmed: pi@octopi:~ $ cat /proc/cpuinfo processor : 0 model name : ARMv6-compatible processor rev 7 (v6l) BogoMIPS : 697.95 Features : half thumb fastmult vfp edsp java tls CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xb76 CPU revision : 7 Hardware : BCM2835 Revision : 0010 Serial : 00000000242c9369 Model : Raspberry Pi Model B Plus Rev 1.2

I get it that you didn't read my reply! And if you use "rasperian lite" I recommend that you upgrade to "Raspberry Pi OS".

cat /etc/os-release

There you can see which OS is on it. Your output only tells you something about the CPU, but nothing about the OS.

you could even try installing PINN

it's in the RPI imager