Besides, Etthereum, what coin should I mine after the merge? I get free power.
You have two options.
1: Wait until AFTER the ETH PoS merge. Wait until video card prices crash as miners go out of business then liquidate their rigs. Then buy cheap RTX 3060's for $200-250 each or RX 6800's for $300-400. With free power, you will probably make a 20%-50% per year return; then hopefully when the next GPU coin gold rush happens, you can make a 200-400% return in a year.
2: Buy video cards now and mine on them, hoping to sell them off right before the PoS merge. You're taking a risk with timing. However, PoS should take at least 6 months. Returns in today's market can be up to 300% at free power.
Switching over to a different coin after PoS will
not work, because the resale value of your GPU will collapse overnight. You
must liquidate before GPU prices crash!
Anyone using this strategy with 4GB cards?.
Those days are long gone. Mine ERG, ETC, FLUX or the best coin for the hardware. Beware that after ETH PoS, all the ETH ASICs like the Innosilicon A10 / Bitmain E9 will be mining ETC/ZIL/MTP/QKC. Your GPU will be competing against ASICs which have no other choice, so expect to make 10x less revenue than you can these days.
BTW, folks who bought ETH ASICs today will be the bagholders if PoS happens in less than a year. Imagine the value of an Innosilicon A10 Pro 750Mh miner plummeting from $14k to just $2k.
If ETH can still be this profitable after all those millions of Asic miners around the world then its possible that other PoW coins will continue from where ETH left off, its only a matter of time, once every coins are worthless to mine the difficulty will start reducing, this is where I will get in.