The weak link is your CPU. You should definitely upgrade maybe.
EDIT: To explain your low usage levels, they're averaged, and threads are swapped about cores really often, so if you're running at 100% on both threads on a 4-core processor, your usage will appear to be ~50%, and such.
EDIT: To explain your low usage levels, they're averaged, and threads are swapped about cores really often, so if you're running at 100% on both threads on a 4-core processor, your usage will appear to be ~50%, and such.
in a perfect world we would all be piles of sand with no ability to form coherent bodies of body