AMD K6-3 Preview

It all started with the introduction of the AMD K5, a processor that was supposed to be superior to the Intel Pentium at a much lower cost and a lower clock speed as well. Unfortunately that introduction was plagued by a nine-month delay that allowed Intel to push forth with the announcement of their Pentium MMX which AMD simply couldnt compete with. Then came the AMD K6, which was supposed to offer performance greater than any Intel processor, once again, at a lower cost. When the K6 was finally introduced, it struggled to compete with the Pentium Pro, and left a minor gap between itself and Intels desktop class of processors, the Pentium MMX.

It wasnt until the release of the K6-2 that there was reason to have faith in AMD again. The K6-2 pulled through as a highly competitive product to the Pentium II, at a lower cost. In response to this threat, Intel released their own low-cost alternative, the Celeron A which once again, put AMD to shame. Throughout their history, AMD has always seemed to fall just a hair short of winning the gold, and in a race where only the winner survives, second place just doesnt cut it.

That brief synopsis sums up the general state of things from 1997 with the release of the K6, to 1998, the year dominated by the Super7/K6-2 platform. While it has been said that history repeats itself, for AMD to repeat the course of events in the past 3 years wouldnt be the most desirable. It is true that AMD has been successful in their ventures, however theyve never really captured the lime light as well as they could have. So what better way is there to start off a brand new year, than with the introduction of a brand new processor that is finally worthy of the AMD name. As we welcome the New Year this holiday season, its also time to introduce AMDs latest concoction, the K6-3.

Officially planned for launch sometime in early 1999, the K6-3 will be the last processor from AMD to be used in a Socket-7 motherboard before they make the transition to their new slot based architecture for the K7. The roots of the K6-3 are securely fastened in the same ground that sprouted the K6-2, in that the K6-3 is based on the same core as its predecessor was. The 0.25 micron chip boasts the same 64KB of L1 cache (32KB data & 32KB instruction set), the same 3DNow! instructions, and the same motherboard requirements as the old K6-2.

AMDs goal throughout the process of revitalizing the Socket-7 platform has been to offer a clear upgrade path to all Socket-7 users, without requiring them to purchase new motherboards, as AMD assumes that if youre going to buy a new motherboard you may be lured away from Socket-7 by a tempting Slot-1 board. In the past, this goal has been met to a certain degree, with the K6, you needed to have a board that supported the unique core voltages of the processor, and with the K6-2 you needed to have a Super7 compliant motherboard in order to get the full benefit of your processor. This time around, AMD simply requires that your motherboards BIOS be up to date with full support for the new AMD K6-2 400 (based on the CXT core) in order to take advantage of the K6-3.

If a higher clock speed was all AMD would provide as an improvement over the K6-2 with the introduction of the K6-3, this review would have come to an abrupt end a few paragraphs ago, however its obviously not. Quietly learning from Intels experimentation with the effects of L2 cache on overall system performance, AMD decided to take a stab at including a set amount of L2 cache on the K6-3 chip itself, and from AnandTechs experience with the unreleased K6-3, it seems as if they put their money on the right bet. Looking at the K6-3 itself, there is one thing youll notice off the bat, the K6-3 is around 1mm thicker than the K6-2whats the reason for that?

When Intel released the Celeron, the lack of any L2 cache dropped the processors business application performance (i.e. Microsoft Office, Lotus Smart Suite, etc) to below Pentium MMX levels. That mistake was critical to the overall failure of the original Celeron processors, although they were generally accepted by the overclocking market, the rest of the world wouldnt accept a processor with no L2 cache. Turning the Celeron name into a success, Intel decided to include a full 128KB of L2 cache on the processor die of the Celeron, which dramatically increased its business application performance, and brought rave reviews from all that touched the new processor, dubbed the Celeron A.

AMDs decision was to include 256KB of L2 cache on the die of their K6-3, while leaving the rest of the design of the K6-2 (with the CXT core modifications) intact, making the K6-3 AMDs Celeron A, with the K6-2 being AMDs Celeron. Thats what makes up the extra 1mm in thickness on the K6-3 chip.