In the 'muscle car' era, the rule was 'more cubic inches', the faster the car. Indeed, the top fuel dragsters were usually ~500 cubic inches and produced ~1200 HP. Over the years, designers learned that far too many other things contributed to HP and Speed. Today, engines are about the same CI size, but they produce considerably more horsepower. A top fuel dragster (or funny car) produces in excess of 7000!
The computer industry has gone through many evolutions, since I arrived in 1983. For me, processor speed is similar to belief that cubic inches were the key to performance. I will defer to CanadaRam and the other specialists, from whom I learn a great deal from. They provide expert knowledge.
I learned Unix from a chap who is among the leaders in Virtual Reality. He took me to the VR lab. They had banks of DEC Alphas, connected as a cluster. As I recall, they had around 50% computational power of current Cray model (which had 1000 Intel i860s). It was obvious, many processors were better (or more practical) than one huge one.
Multi-core, Multi-processor computing has not began to exploit the resources available. When you factor in the OS, and finally the applications, processor speed is not the issue. I can write a piece of **** application, and look like a genius. That is because the hardware will often allow me to disregard good programming technique. The user will not know that the .05 second difference even exists. But, the cumulative effect of many programmers doing this, produces things like ( fill in the blank ).
There are so many improvements to be made in system architecture, and software design, processor speed could be viewed as a distraction, rather than a goal.
