I've been mining ETH on Minergate for about 4hrs but I can't see anything adding up to my balance.
I have an NVidia GTX1070 producing an average of 27Mh/s. Any idea if not seeing anything after a few hours is normal or there is something wrong?
Do you know which one you have selected?
You'll need to in order to have an idea of how often you're going be receive payouts. I've read that people have gotten payouts quite regularly then it stops all of a sudden. Completely dependant on your selected payment model. For example, PPLNS will give you wide fluctuations in your 24 hour payout, but for hardcore miners,the law of large numbers states you will earn more this way.
Any idea if not seeing anything after few hours is normal or there is something wrong?
You may have a corrupted DAG file. You'll know if you've suddenly been receiving only 'bad' shares. If this is true, then delete your DAG file and restart the miner:
Path on Windows machine: C:\Users\%user%\AppData\Local\minergate.ethash-minergate