A week ago Intel launched its latest range of Pentium 4 processors. What sets these new chips apart from their predecessors is support for 64-bit data execution on top of the 32-bit support.
However, this is not the only change. The Level 2 cache has been doubled to 2MB and Intel is now offering what it refers to as ‘enhanced’ SpeedStep technology.
Intel has launched a wide range of new Pentium 4 chips, starting with the 630 at 3GHz, the 640 at 3.2GHz, the 650 at 3.4GHz and finally the 660 at 3.6GHz. All these processors will operate at an 800MHz bus speed and have 2MB of level 2 cache memory.
The top of the range chip will be the new Extreme Edition which operates at 3.73GHz and has a 1066MHz bus. The new Extreme Edition differs not only by supporting 64-bit operating systems, but also with its cache size, which has actually been reduced in total by 512KB. The reason for this is that the older 3.46GHz had 512KB of Level 2 cache and 2MB of Level 3 cache, while the new 3.73GHz processor only has 2MB of Level 2 cache. The micron process used on the die has also shrunk to 90 nanometre compared to 130 on the 3.46GHz part.
All of the new processors incorporate XD bit (Execute Disable Bit) technology. This is Intel’s equivalent to AMDs Enhanced Virus Protection, and prevents the execution of certain types of buffer overflow worms and viruses. This is not a new feature, as all Intel processors with the J suffix have it as well as later models.
Interestingly, Intel has not launched a 3.8GHz part at this time, so the 570J is still the fastest Intel processor in terms of clock speed that you can buy. But it’s not really a surprise move as Intel has already stated that it is moving away from pure clock speed increases and adding other performance enhancing features.
Intel refers to its 64-bit implementation as EM64T or Extended Memory 64-bit Technology. This enables the processors to address more than 4GB of memory. However, this is not the only benefit of going to 64-bit. A 64-bit operating system running 64-bit code will give you a performance boost over a 32-bit operating system running 32-bit code. The main reason for this is that the CPU address register is larger than on a 32-bit processor, which in turn enables more data to be processed. To put it in a simple way, a 64-bit processor provides faster performance than a 32-bit processor by handling twice as much data per clock cycle.
As you most likely are aware Intel is playing catch up on the 64-bit desktop market, since AMD have had products available for over a year and a half now. The 64-bit implementations from AMD and Intel are very similar, so there should be only minor tweaks that would be needed to create 64-bit operating systems and applications that will work well on both platforms. None of this has made any difference as we have yet to see a finished 64-bit version of Windows XP and it is this that holds the key to mass market 64-bit desktop computing.
Intel has of course already flirted with 64-bit computers with the introduction of the Itanium processors a few years back, but these were never intended for desktop use. 64-bit computers stretch even further back as DEC launched 64-bit machines back in the early 90’s with companies such as HP, Silicon Graphics and Sun all having products available during the mid to late 90’s. Neither of these products became hugely popular outside of their markets mainly due to very high purchase costs.