What's clock speed got to do with it?

My CPU's clock speed is faster than yours. This is what I hear all the time it seems. People are always judging a machine by how many GHz their CPU runs at. This is far from the correct way of viewing speed when it comes to computers. If this was the case then a Pentium 4 with hyperthreading that ran at 3.0 GHz must be better than an i5 that runs at 2.66GHz, right? WRONG! When it comes to speed there are so many other factors to take into account. First you have your Front Side Bus (FSB). Basically this is the path that information takes along the motherboard on its way to its next destination, whether that be from the CPU to the RAM, or the RAM to the Hard Drive. The CPU can calculate so much information (clock speed) at a given rate. This information is useless if can't get to its final destination very quickly. You could have a fast CPU but a slow FSB and slower memory. What would be the point? Take a look back in time. Do you ever recall seeing a 5 GHz computer on the market? Well if you did it was probably an extremely over inflated number, or just plain ole false advertising.

Just take a look at a couple of newer CPUs that have hit the market. You have the Intel Core i5-650 that runs at 3.2GHz and the Intel Core i5-750 that runs at 2.66GHz. Which one do you think is faster? Yes the i5-650 has a faster clock speed rating, but in benchmark tests the i5-750 is able to run faster. This could be due to the amount of L2 and L3 cache on the chip itself, along with the actual architecture of the CPU.

In short, there are just so many other factors to determine how fast your computer is other than how fast the clock speed of your CPU is. Just think of this, there are plenty of 4 cylinder cars out there that can beat an 8 cylinder car in a race.

check out the benchmark scores:
http://www.cpubenchmark.net/cpu_lookup.php?cpu=Intel+Core+i5+650+%40+3.20GHz
http://www.cpubenchmark.net/cpu_lookup.php?cpu=Intel+Core+i5+750+%40+2.67GHz