Go for it with your 3090, it will perform well and the mining won’t hurt it at all . You can only mine Ethereum on a gfx card with 5gb or higher. Both the amd rx 400/500/5000 series as the nvidia gtx 1060 6gb and upwards are good for eth mining. But today Ravencoin went from 5 dollarcent to 19 dollarcent.
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Single 3090 mining at 57.4Mh/s @ 350W .5 Mar 2021
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