Monday, September 18, 2000

Introduction

These days, it seems that every maker of x86 processors, and their monkey's uncle, are selling a 1GHz CPU. Because of this, we've come to the conclusion that its about time that we got down to the business of comparing the various 1GHz offerings on the market in order to gauge their actual, relative performance. So, with that in mind - and without further ado, we present out comparative test of the Intel 1GHz processors, the "Classic" Athlon 1GHz, and the Athlon "Thunderbird" 1GHz, following a brief description of our contestants.

The Intel Pentium III
Coppermine FC-PGA 1GHz.

Save for its clock frequency, and its slightly elevated Vcore voltage, nothing distinguishes the 1GHz incarnation of the PIII "Coppermine" from its fellows. Fabricated on a 0.18 micron process, the 1GHz "CuMine" draws 1.70v in Vcore voltage, compared to the 1.60v of all of its siblings - save for the 933MHz rendition, which itself draws 1.65V. One thing that has to be noted, is that the 1GHz "CuMine" is designed for a 133MHz Front Side Bus, and not the 100MHz bus that many believe.

In fact, there is no version of this chip that is designed exclusively with a 100MHz bus in mind. By incorporating Intel's ATC, and ASB technologies, the 1GHz "CuMine" profits from many of the small core refinements that Intel has made over the years. Still, those two acronyms may not exactly be ringing any bells, so it seems fair that we take a brief interlude in order to explain the two:

ATC (Advanced Transfer Cache)

The L2 ATC (Advanced Transfer Cache) is a small block of L2 cache memory that is integrated into the very body of the CPU, and which operates at the very same frequency as the processor core itself. Some of its more interesting features include (it is/it possess a):

By moving the L2 cache onto the processor die, Intel has reduced the amount of needed to fetch frequently or recently used instructions & data from memory. The integrated cache also permits for dedicated 64-bit access.

ASB (Advanced System Buffering)

"Advanced System Buffering" consists of a series of optimizations performed on the system buffers, and on the waiting order of the queue, which results in an overall improvement in performance for systems using 100MHz, and 133MHz buses. This feature includes

To sum things up, the Pentium III FC-PGA 1GHz is produced using a 0.18 micron manufacturing process, includes 256K of full-speed L2 cache, draws 1.70v of voltage, and includes nearly 30 million transistors.

Next: The AMD Athlon processors