It's a common question to see how an AMD CPU stacks up to an Intel. As gaara said, a 3700 is somewhat similar to a 3.7GHz Intel. It is difficult to compare because of Dual-Cores and because of other things that aren't apparant from looking at a clock speed, like cache, instruction sets, and the actual architecture of the CPU as well.
If you are looking to compare which CPU is 'better' than the other, look at benchmarks. Benchmarks are the only way to actually tell for sure, before buying, what chip to buy.
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