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sorry for the delay, looking at the photo it appears as if the cracked corner is not cutting any supply lines
so that board should be OK,
You may have a bad main board, to confirm you will need to test the power supply
on this you tube video here it shows how to turn on the power supply and check the 24 volts output voltage, if your power supply turns on when you jump 5volts pin to the p/on pin (see video)