AMD aren't "better" than Intel O_o Price/performance wise they are.
Intel have better architecture in their processors, they generally have larger caches, they have hyperthreading... they're more advanced than AMD and their chips run cooler.
A 3GHz AMD chip VS 3GHz Intel Chip, the intel will win because they do more calculations per second than an AMD chip could, only downside with Intel is they're infamous for their prices.