which is the average temperature inside a pc case ?

[Flaviu Dobrescu]

I'm worried because my pc tend's to get hot. Sometimes when im gaming, in the case temperatures reach 45.7 Celsius, is that normal ?

 

[menetlaus]

Case temp isn't a big concern. Where you need to be concerned about temps are the heat producing components (CPU, GPU, power capacitors/etc, hard drives, PSU, and such).

Granted the higher the temp inside the case - the hotter each part wil run (and will shorten the average lifespan for the part).

Try using an application that can show CPU/GPU/HDD temps as they are what you really need to watch out for.