GPU ETH mining beats cost of electricity by 400-800% at $0.09-0.12/kWh, even with various losses and a single card. (300W total system draw for $24/month and $100-200 USD output)
I've got a 1660 that I sometimes set to mining when I'm not doing anything else with it. I use Nvidia-smi to set the power limit to 75W to keep the fan from being audible.
A full month of mining would net about $50 in ETH for $4 in electricity. If you are buying equipment just to mine, it's probably not a good plan. But if you already have it, sure, it's pretty profitable.
