System temp = case temp = motherboard temp.
The motherboard has a sensor on it that programs call various things, but they're all the same.
When people talk about their CPU temperature, they're talking about the CPU-die temperature. Also, I think you may have put too little/too much paste on the CPU. I have the 7000B also (installed with Arctic Silver 5) and my case, by nature, has no fans per se. The CPU idled at 40C without any fans until I modded my case. So even if you have no fans in your case, the CPU should idle at about 40C--probably even lower since my case is small. Here is a guide
to putting on Arctic Silver, and it could probably be applied to regular thermal paste as well.