Beginners • Waht should I see when I boot from an imager-created SD card

I am struggling to get an old but prveiously unused Raspberry Pi4 B working "from scratch".
I have a screen, keyboard and mouse connected to a new RPi4. I have tested this with a 128GB SD card (it has a specialised image) from another RPi4 and it works.
I used "Raspberry Pi Imager" with another 128GB SD card to generate something I expected to boot and provide me with some kind of interactive experience. I see a "Rainbow screen", at least once sometimes twice or three times - with the red led going out briefly sometomes before the second/third "Rainbow screen". The green led continues to flash sporadically and randomly - it doesn't settle to correspond with the description of "error codes" I have read about. Basically, I end up with a completely black screen. What should I be seeing? Surely some text, prompt etc.

Some further notes:
- I select Raspberry Pi OS (recommended twice!)
- I have tried with two different 128GB SD cards. Both work fine on other equipment and pass Windows scan tests
- I have used two different USB-SD card interfaces
- I have used two different PSUs one a RPi one and another beefy one
- I have tried with and without the set-up options

Any help would be appreciated.

Statistics: Posted by jegsav — Tue Apr 29, 2025 10:04 am

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