for the gpu anything under 65 C is okay for 24 hours a day as far as processor temps i like to keep my processor under 50 C. Minergate is trash Yes you're new and Yes i started there too but go to ethermine.org, Slushpool, or somewhere else.
Exactly what this guy said. Actually you can even push it up to 70. But in general, the principle is that the lower the temps, the better for your GPU.
The next question you might ask is 90-100% fanspeed ok? Yes. Thats better than running your GPUs at high temps. All this information and more is available on google btw.