"Enabling this feature allows the caching of the motherboard BIOS ROM from F0000h to FFFFFh by the processor's Level 2 cache. This greatly speeds up accesses to the BIOS.
However, this does not translate into better system performance because modern operating systems like Microsoft Windows XP do not need to communicate with the hardware via the BIOS. Current operating systems make use of drivers to access the hardware directly.
Therefore, it would be a waste of the Level 2 cache's bandwidth if the motherboard BIOS was cached instead of data that are more critical to the system's performance.
In addition, if any errant program writes into this memory area, it will result in a system crash. Therefore, it is highly recommended that you disable this feature for better system performance.
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Quelle:
http://www.rojakpot.com/