Sorry, I meant to say Power Limit, by adjusting that it actually undervolts the card that you're using. You can technically do whatever you wish for the temp of your card as long as you don't mind it dieing faster or slower on you, it's really up to you. You can have it running at 100c 24/7 non stop for months on end and it might be fine if you get a good bin on the card, but for most of us, we prefer to keep the temps down to 65c if not 70c max, reason being is heat output, and electricity costs. The lower the temperature, the better, anything under 40c mining on air is literally a crazy good temp(Mostly achievable through watercooling)

The reason why I said to stay away from CPU mining on minergate is because if you only get that little amount, you need to factor in the electricity cost of your rig per day(Total TDP, and cost of electricity e.g. $0.12/KwH) If your cost of electricity coming from your rig doesn't even out in your earnings or if your not making more than the cost to run your rig, its not worth mining such little worth of cpu mining or miner gate.

Also the reason why I suggest staying away from minergate is due to the fees, most pools offer better fees rather than minergate, plus they'll actually send it to your
"Own" wallet, not a wallet in their servers then charge you extra just to take it out of "Your" wallet to send to another wallet you "own". Pools will send it to any address you want when mining(which doesn't go to the pools wallet, it goes to your wallet without the extra fee of hosting a wallet in their server)

I'd recommend staying away from NiceHash unless its the only option you have as well, reason being is you could probably mine better at different pools like Yiimp, or Zpool(Not really recommended, but better than NiceHash) or even SuprNova.cc . It all depends on your mining hardware.

Also to mine safely it depends on your computer's hardware quality, the biggest thing to not skimp out on is the Power Supply, make sure its a trusted brand and is 80+ Gold rated or higher, anything less and your going to end up replacing it sooner rather than later.(You can argue with me on that, but just for safety reasons go with Gold or Platinum, shoot if you can get a Titanium for the best.)