Dead system? Will not turn on only a White flash and click

I tried everything to make it book as in hold command+R etc…

I also tried reseating the RAM, changing the RAM entirely with new RAM as well as changing the HDD. I also unplugging the battery for a day or two and holding the power button while the battery is unplugged and still nothing.

Only a White LED flash and a click. The battery can still charge and hold a charge so I don’t think its a battery issue either, but whenever I connect the charger the system tries to boot but still only the flash and a click.

I’m worried my poor Mac is dead.

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Restart your system holding the T key, are you able to see the FireWire & Thunderbolt icons on your screen (target disk mode)?

Reference: Mac startup key combinations

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