1. Your PC CAN send 500% volume. It’s just that the feature is blocked by default.
2. It is blocked by default because your wiring has an operational range of power that it can run without being damaged. Sound increasing softwares simply amplify the current. they don’t do anything magical. This doubling of current will put the power passing through beyond the safe zone and will eventually damage your headphones or motherboard circuitry.
I would recommend never increasing sound beyond 100% though. If the sound is low, louder speakers and headphones.
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