Introduction

The megahertz race ended years ago and we moved into a technology race. It's not just about how many megahertz you can squeeze out of a chip, it's how efficient you can make the CPU; how well two or four cores talk to each other; how efficient the cache is; the quality of the memory interface, the PCI-E interface and the GPU interface.

When you look for a new processor, the naming of CPU and just that raw MHz listing is not enough to go by.I see it all the time. People still think that number next to the name is the MHz rating. But it stands for Performance Rating.

The Performance Rating first debuted in the market in 1996 when both AMD and Cyrix introduced a PR rating as a marketing scheme to help sell their CPUs against the dominating force of Intel's Pentium processor. Both companies used a limited number of benchmarks in which their CPUs were faster than Intel's, to rate the speed of their CPUs when comparing them to an Intel Pentium. Many people mistakenly believe that PR stands for Pentium Rating. It is not the case and never was, although the Pentium was the basis for comparison when calculating the PR rating of those early AMD and Cyrix CPUs. Cyrix continued with a PR rating for many years but AMD dropped it when they launched their K6 processor.

The true megahertz wars started when real competition came from AMD in the forum of the Athlon processor. If I remember correctly, the Athlon launched at about 500MHz and quickly shot up to be the first CPU to break the GHz barrier. I remember receiving the first 1GHz Athlon CPU in the country and having to install it and set up a test system on AMD's booth at a Sydney IT show. I ended up finishing getting everything set up at about 12:30am the morning before the show was to open. People were blown away to see that barrier finally broken.

Both Intel and AMD played the megahertz game for a number of years, doing little to nothing to the design of their actual CPU cores, apart from increasing the voltage and clock speed and attempting to decrease the die size. The megahertz race came to an end with Intel's limit of 3.4GHz with their Prescott core. Anybody with experience of those CPUs will remember how hot they used to run. People definitely didn't appreciate the fans and cooling requirements. Both AMD and Intel had hit the limit and had to rethink CPU design to increase performance, rather than just increase voltages and cooling methods like common overclockers. The first thing they did was to start increasing the amount of cache and then to increase the number of cores on the one physical chip. This is when the PR rating was re-introduced by Intel.

Is the PR rating a good method to judge the performance of a CPU? No, not really. PR rating has given the marketing teams at Intel and AMD creative license. The majority of computer users don't understand what a CPU is let alone a performance rating vs GHz measurement. This gives the manufacturer's the ability to suggest to their customers that they are getting something far superior to what they are actually getting. The only true way to measure the speed of a CPU is to directly compare it in benchmarks and real world tests.

Real world tests are important because even benchmarks are the subject of creative marketing from CPU manufacturers. Large amounts of monetary investments are made with benchmark companies to ensure that CPUs are optimized for the tests. It's kind of like WWF wrestling - would you really bet on a fight where the outcome was pre-planned and staged?

One of the biggest misconceptions about CPU manufacturers increasing the number cores, is that the performance of the CPU increases by the same measure. Is this really the case? Are you going to see any real world performance differences by spending five times the amount of money on an Extreme Edition CPU?

We will not only show you real world and synthetic benchmark figures but we'll show you what the CPU cores are doing during these tests. Let's get started.