you can't make it to 100%
Because the game builders have made the game programed to 30fps
if you want to increase it the hard disk's speed may needed!
I think the gpu usage will go up 100% but not at all the time sometimes
Increasing resolution increases cpu usage!!
What manufacturer power supply and output do you have in your system? Aside from that, I don't see anything with your system that would be limiting you to such low frames per second rates. Hardware wise, you're fine.