Readers who have owned or experimented with Intel's Pentium II line of CPUs in an overclocked environment are well aware of the difficulties associated with the CPU's external ½ core speed Level 2 cache.
Comprised of two 256Kb SRAM modules, the L2 cache on the Pentium II and Pentium III CPUs is speed rated to match the default (stock) speed of the CPU core they're mated to. Simply put, the speed of the L2 cache determines the final speed at which system-wide stability will occur.
There are no ways around the finite speed limits of the L2 cache modules.
Some choose to disable their L2 cache within their mainboard's BIOS, effectively shutting it down and eliminating it from the equation. The problem with this course of action is that the L2 cache is highly utilized in both 2D and 3D applications, and performance of the overclocked non-L2 cache enabled system falls far below the stock L2-enabled rig.
Occasionally you'll hear reports that someone has overclocked their P3 CPU to 750 or even 800MHz, but the reality is that the L2 cache has been disabled in order for that speed to be obtained. By disabling the L2 cache, a 750MHz P3 is now handicapped to a performance level that equals 600MHz at best.
Not recommended.
Therefore, the challenge becomes not only to push your P3 CPU to the limits of its core, but also the limits of its L2 cache.