With dual core enabled Dolphin uses 2 CPU cores, which usually makes it hit 50% on a quad core system. However, in many games the amount of work each core must do is unbalanced, so one core could run full (25%) while the other only uses 15%. However from what I've seen, most game will reach 50% if they are running below their restricted speed, so it's not easy to say if your CPU is somehow restricted (for example power saving settings on laptops).
Specs: intel i5 3570k @ 3.4GHz;
16Gb RAM; Raedon HD 7900;
Win8 64-Bit
16Gb RAM; Raedon HD 7900;
Win8 64-Bit
