History has shown us that where the presence and performance of the L2 cache truly becomes apparent is under business applications and not games.  This can be proven by the fact that comparing a cacheless Celeron running at 300MHz to a Celeron A outfitted with 128KB of L2 cache also running at 300MHz results in two different pictures in business and gaming situations.  Under Quake 2, there is very little difference between the two processors, however under Winstone the difference is greatly exaggerated in comparison.

Business Winstone Comparison - The Effect of Cache
The Celeron A takes on the Celeron

The reason such a performance difference is present under business applications is because those applications often times continuously repeat certain operations over and over again, and can usually fit in to the L2 cache of the system, whereas 3D games, like Quake 2, usually consist of FPU intensive math calculations with very little redundancy in terms of operations.  The above comparison taken from the Intel Celeron A Review also shows that the faster L2 cache of the Celeron A, although it is 1/4 of the size of the Pentium II's L2 cache, does provide for greater overall system performance due to its sheer clock speed advantage. 

With that said, it should now make much more sense that a system with a faster L2 cache would perform much better than a system with a slower L2 cache.  If you look at the K6-2, with it's L2 cache operating at 100MHz regardless of the clock speed increase, its performance under Winstone (98 or 99) is going to increase with clock speed, however the increase is going to provide a diminishing return as the clock speed increases further.  Intel made a smart decision by including the L2 cache on the cartridge of the Pentium II in that as the speed of the processor increases, the speed of the L2 cache will also increase, making every step up in a clock speed correspond with a hefty increase in overall business application performance as well.  The downside to this approach is naturally, cost, however as Intel proved with the integrated L2 cache of the Celeron A, such an approach can be made in a cost effective manner.  For comparison's sake, let's see how that table from above changes with the introduction of the K6-3 which will feature a full 256KB of L2 cache operating at clock speed ala the Celeron A: 

Table 2: Cache Clock Speed Increase vs Processor Speed Increase w/ K6-3
Clock Speed in MHz
@ 300MHz
Clock Speed in MHz
@ 450MHz
% Clock Speed Increase
L1 Cache L2 Cache L1 Cache L2 Cache L1 Cache L2 Cache
AMD K6-2 300 100 450 100 + 50% + 0%
AMD K6-3 300 300 450 450 + 50% + 50%
iCeleronA 300 300 450 450 + 50% + 50%
iPentium II 300 150 450 225 + 50% + 50%

This should paint a more vivid picture of why AMD had to release the K6-3 in order to survive until the release of the K7.  With each step towards a higher clock speed, the performance difference between the P2/Celeron A processors and the K6-2 would increase to a point where the K6-2 would eventually become a noticeably slower alternative, in order to avoid that, AMD chose to integrate 256KB of L2 cache onto the K6-2, and slap on the K6-3 label.  A smart move by AMD, however the real question will be whether or not it'll make it into the hands of the consumer in time to be effective. 



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