Neil,
I also could not identify the PCB P/N in the 450 fw. I have no more the 450, but the PCB P/N (that have similar screens as the Etrex30) is not informed in the Diagnostics Pages (see link). If you or anyone has any other tips on how to discover this P/N I'll stay more relaxed for flashing the G5, which I have two options: either turns it into 450, or sell your pieces (more likely), since that is useless as gps.
Tks

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