Is the 45-55°C temperature while doing nothing or playing? the one you posted , beside check your task manager do you see any program using alot of pc performance? "CPU usage" ?
I recommend you run the game and check your CPU temperature and let us know , use this software to get CPU temperature
Real Temp is a temperature monitoring program designed for all Intel processors. It runs on 32 bit and 64 bit Windows without installation.
www.techpowerup.com
Also check if any of your cores are parked or not
Start Task Manager- Performance - Resource Monitor - CPU
The Graphics on the right side will display text next to the CPU