For most people, not much. Your earnings depend largely on how good your GPU is. My work computer generates about $0.31 per day in Bitcoins, but if you have a gaming PC with multiple high-end GPUs, you could make $1.50 to $5 per day or more .
Read moreWill mining damage my laptop?
Yes, via overheating of your GPU and CPU and overloading of your power supply . Do NOT try mining on a laptop – almost guarenteed to kill it very quickly as laptops are NOT designed for high-load continuous usage (using a laptop to control a USB-interface miner is OK as that doesn’t put significant load on the laptop).
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