Sustaining Moore's Law - 10 Years of the CPU


Timeline: 2002

2002

While AMD had sought to counter the high clocks on the Pentium 4 with a new version of the Athlon, featuring the Palomino core in late 2001, 2002 was the year that the competition between the two competitors erupted into a full blown contest as both the Pentium 4 and the Palomino became widespread in retail. AMD was finally forced to respond to Intel's Pentium 4 and its burgeoning clock speeds. Hence, AMD's Palomino core, which was dubbed the Athlon XP came with a new PR (Performance Rating) that removed any overt mention of clock speeds from the Athlon's model name. Instead, the new rating compared the relative performance of the Athlon XP against the 1.4GHz Thunderbird. This was to counter Intel marketing that its processors had higher clock speeds and hence the implication that it was faster. This PR rating system has been used by AMD ever since, even though the various micro-architectural changes since have made this quite irrelevant.

The Palomino had greater power savings than the warmer Thunderbird core and performance obviously was another step up, particularly as AMD started to include Intel's SSE and its own 3DNow! instruction sets. It was also available in a MP version, which officially supported multi-processing (dual in this case) with the appropriate motherboard of course. This lead to an interesting modding experiment by us, where we tried to see if the Athlon XP could work as a MP version on a AMD 760MPX motherboard. Although the BIOS would try to lock this 'feature' on detecting our Athlon XP processor, we found that "modifying the CPU to run in a dual configuration is much simpler than unlocking the multipliers. Just use conductive paint to connect the two pads together." And voila! We could get the motherboard to run our Athlon XP processors in a dual processor configuration successfully. (If we could only do that now and unlock the Phenom X3 into a full fledged Phenom X4.)

On the Intel front, 2002 was the year the Pentium 4 started to break clock speed records, with its Northwood revision breaking the 2.0GHz mark then the 3GHz mark. This was aided in part by Intel moving to 130nm process technology and the company also introduced Hyper-Threading to the consumer arena with a 3.06GHz model. Our first glimpse of a Northwood core came with a 2.53GHz version that left "no doubt that the Pentium 4 is now holding the crown of performance."

As we mentioned, the 3.06GHz Pentium 4 was the first consumer processor with Hyper-Threading, which aided in the execution of multiple threads by fooling the operating system into thinking that there was indeed two cores onboard, thereby allowing the scheduling of more than one thread. Hardware Zone took a long look at this new technology, previously available only on Xeon servers and our conclusion was very positive:

In our individually concocted tests, we managed to show an appreciable gain in performance under heavy multi-tasking environments. This is indeed a very powerful testament of the capabilities that Hyper-Threading offers. Certainly, we're very sure that this would give users a more enjoyable and productive use of their PC, especially users who frequently need to perform multiple tasks at one time.

"Hyper-Threading technology is possibly the best thing that has happened to the desktop processor since the the introduction of the Pentium series. For that, we're giving it our Most Innovative Product award.

Since its heydays with the Pentium 4, the importance of Hyper-Threading has declined with the emergence of dual and quad-core processors. However, Intel's new Atom processor for the low-power mobile devices segment saw a return of Hyper-Threading, since the Atom is a single-core processor. This technology is also set for a major revival with Intel's next generation Nehalem processors, which have up to eight processing cores and with Hyper-Threading, expected to execute many more threads in parallel.