I think you are talking about some Empty Boards which cannot be
power on, i.e. as you mentioned, no CXC xxxxxx on the screen,
right ? This could be happened if the flash Chip inside is 'really'
blank...., e.g. change a bad flash chip with a new one.
For my experience, you can physically cloned the flash chip with
a same model (by universal programmer) and write by SE Fighter!
Cables
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