誠懇建議不要再讓這個 second level cache 再繼續誤導下去了。

Detailed Explanation of SecondLevelDataCache
http://support.microsoft.com/kb/q183063/

This is not related to the hardware; it is only useful for computers with direct-mapped L2 caches. Pentium II and later processors do not have direct- mapped L2 caches. SecondLevelDataCache can increase performance by approximately 2 percent in certain cases for older computers with ample memory (more than 64 MB) by scattering physical pages better in the address space so there are not so many L2 cache collisions. Setting SecondLevelDataCache to 256 KB rather than 2 MB (when the computer has a 2 MB L2 cache) would probably have about a 0.4 percent performance penalty.
(以上資料節錄自 Microsoft 知識庫)