My demo setup= FX8350 OC'd
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1. I started off with NiceHash Miner 2.0.11 and Bitcoin Core 0.15.0. I'm pulling in 450 H/s on the Equihash. Is that decent? How does H/s translate into MH/s?
If you mine Bitcoin (algo = SHA256) you are doing it wrong. Bitcoin mining is not for GPU in 2017. H/s is 1/1000 MH/s.
Find an altcoin to mine and, if you want to, trade or convert to BTC. ETH, ZEC, XMR may be some candidates, go to altcoin mining section and ask there.
Every coin (more or less) has its algo. So the H/s for one algo is good and for another algo is bad. Use some profitability calculators like whattomine.com
Also if you get H/s for one algo you may get kH/s on another algo... all differ.
2. I want to mine Ethereum. I got GETH up and going but I haven't seen a decent set of instructions on the language. Can you please walk me through step by step because the youtube videos suck. I can get it up and running, but wh. wtf is it doing, where do I enter in my Ethereum wallet ID and all that good stuff?
Sorry, ETH is one of the few coins I didn't tray to mine. Go to altcoin mining or even on ETH threads and ask there.
3. Is Linux more profitable due to less overhead on the GPU?
Some tell that Linux is better for mining because is more stable and drivers work better. But it's not the only factor.
There's also a Linux based OS for mining, just search around and you'll find it, it may help.