Disable both,READ BELOW.
System BIOS Cacheable
Selecting Enabled allows caching of the system BIOS ROM at F0000h-FFFFFh in the L2 cache, which greatly speeds up access to the system BIOS. This does not improve system performance as the OS does not need to access the system BIOS much and if any program writes to this memory area, a system error may result. Thus, it is more efficient to allocate the cache to data so the recommended setting is DISABLED.
Video RAM Cacheable
Same idea as above, so the recommended setting is DISABLED.