Why your PC is now obsolete: the new Intel Core 2 Duo
According to the authoritative AnandTech (emphasis his):
Intel’s Core 2 Extreme X6800 didn’t lose a single benchmark in our comparison; not a single one…Compared to AMD’s Athlon 64 X2 the situation gets a lot more competitive, but AMD still doesn’t stand a chance.
These chips are not only screamingly fast, they also use less power. This is critical nowadays, as businesses get a double-whammy on their electricity bills — power to run the computers, and power to run the air conditioning.
The Core processor is so good because Intel doubled the very high-speed working memory on the die itself (to 4MB of L2 cache). Combined with the really fat pipe (a bus 256 bits wide) and extensive prefetching, the dual cores stay very busy. To be technical:
The Core architecture’s L1 cache delivers about twice as much bandwidth… while its L2-cache is about 2.5 times faster than the Athlon 64/Opteron one.
The chips also use “bigger, smarter circuitry that can do a lot in parallel” to combine steps when possible (macro- and micro-op fusion), saving about one operation in ten. This also applies to multimedia (SSE) processing (which is bigger) and advance loading (which is smarter).