50C idle or 50C at load?
For idle thats pretty hot IMO, but at full load it shouldn't be anything to worry about.
Thought I taught you how to read, wait no I didn't

but either way:
[. . .] and just wanted to know if idle temps around 40-50C with the side panel on were normal.
I don't know how hot it should run, but it wouldn't hurt to lower it some. 40-50C won't kill it, but cooler is usually better.

My AMD usually run 30-35 idle, assuming the readings are correct, but I keep it cool in the house and case.
Some things to make sure aren't a problem:
-Insufficient Thermal Paste/Grease
-Insufficient Airflow in case
-An Overclock of the CPU (in which case heat will happen)
-Hot ambient temperature (inside and outside case)