Dolphin uses a very large amount of CPU resources. You are wrong in your assumption that it uses a small amount like any computer game.
Let me explain more in-detail
To execute an instruction in an emulated game, you must translate that instruction and then run it. This is fine for emulating machines that use small amounts of instructions per second, like a NES, or a system that you don't need to translate very many instructions for, like an XBox, but something that is neither takes a really long time. It usually takes multiple instructions to translate the original instruction to something that the computer can use, meaning that a single instruction might end up taking 10 times as long to run as normal (though, as far as I know, it's actually usually a little longer)! Now, with a system where you must emulate the CPU, GPU, and SPU all at the same time on the CPU (unlike the NES, in which all are the same processor, or the XBox, which, again, is very compatible), it takes a lot of power to run at "normal" speeds. The GC and Wii are systems like that.
But, how fast is your processor? Well, it's a bit faster than my Athlon II per-clock. My Athlon II puts out 2 instructions per clock on each core at it's very peak speed, so you're not getting very much speed (4200MIPS at the very fastest), and it's definitely not enough to emulate a modern system. And then, there's some things about Dolphin that make your CPU slightly faster than the more likely 2100MIPS peak, but windows uses up a lot of processor time.
Let me explain more in-detail
To execute an instruction in an emulated game, you must translate that instruction and then run it. This is fine for emulating machines that use small amounts of instructions per second, like a NES, or a system that you don't need to translate very many instructions for, like an XBox, but something that is neither takes a really long time. It usually takes multiple instructions to translate the original instruction to something that the computer can use, meaning that a single instruction might end up taking 10 times as long to run as normal (though, as far as I know, it's actually usually a little longer)! Now, with a system where you must emulate the CPU, GPU, and SPU all at the same time on the CPU (unlike the NES, in which all are the same processor, or the XBox, which, again, is very compatible), it takes a lot of power to run at "normal" speeds. The GC and Wii are systems like that.
But, how fast is your processor? Well, it's a bit faster than my Athlon II per-clock. My Athlon II puts out 2 instructions per clock on each core at it's very peak speed, so you're not getting very much speed (4200MIPS at the very fastest), and it's definitely not enough to emulate a modern system. And then, there's some things about Dolphin that make your CPU slightly faster than the more likely 2100MIPS peak, but windows uses up a lot of processor time.
in a perfect world we would all be piles of sand with no ability to form coherent bodies of body