My GPU usage goes up to 100%, but CPU usage stays around 20%. Is that low CPU usage? Seems kinda low to me, although it's not like I know too much about this kind of thing.

Specs:

ATI Mobility Radeon 6570
GPU clock rate: 600MHz
GPU memory clock: 1GB

Intel core i7 2630QM @ 2.00 GHz 2.00 GHz (it says that twice, so I did too)

RAM: 8.00 GB

Yes, that is low CPU usage.

The reason is because your GPU is pretty slow. Especially when you compare it to your i7-2630QM (which is a pretty new, and pretty good CPU for a laptop). That means that the GPU is the bottleneck to get higher framerates. Compared to the amount of work your GPU needs to do for every frame that is displayed, the CPU is done with its work in 20% of the time it takes the GPU to render a frame.

Not much you can do to change that. If you have acceptable framerates, and all the eyecandy you want, then there is nothing to complain. If you want higher framerates, you could tone down, or turn off, eyecandy (no AA, no high-res textures, going from Ultra -> High or even Normal settings, etc).

I know a little bit more about this stuff now. Thanks :3

It's too bad I don't have a desktop instead; I could just get a new GPU or overclock.

Yes, this is one of the main benefits of having a desktop. When you want to upgrade, you can upgrade just specific components. And when you want a "real new PC", you can still reuse many components. E.g. I am going to buy a new CPU this week. When you buy a new CPU, you almost always have to buy a new motherboard and new RAM. But I can reuse my harddisks (and my SSD). I can reuse my monitor (good luck with that when you wanna upgrade your laptop). Reuse my powersupply, mouse, etc. I could even reuse my case, but I finally want a new one.

There's benefits to both laptops and desktops. It depends on where your priorities are. I sometimes regret I can't lay on my couch while surfing. But I have a special desk, special chair, in a separate room for my PC. Ideal for long gaming sessions. I wouldn't want it any other way.