I am using a Ryzen 1600, getting around 450 h/sec. Using 12 threads. The CPU temp stays at around 50 deg.
Could you say more about your config, please? How much RAM (sticks and capacity) do you have?
I'm getting about 530 h/s (cpuminer-sse42.exe v3.7.8) on my old crappy Xeon 3440 (Nehalem arch, LGA1156, 4C/8T) @ 3,2 GHz with 2 x 4 GB of RAM.