TYAN Tempest i5400XT S5396 User Manual page 40

does not necessarily make the system perform better because the OS does not
need to access the system BIOS often.
As such, it would be a waste of L2 cache bandwidth to cache the system BIOS
instead of data that are more critical to the system's performance. In addition, if
any program writes into this memory area, it will result in a system crash. So, it
is recommended that you write protect this area for optimal system performance.
Uncached / Write Protect
Cache Video BIOS Area
This feature is only valid when the video BIOS is shadowed. It enables or
disables the caching of the video BIOS ROM at C0000h-C7FFFh via the L2
cache. This greatly speeds up accesses to the video BIOS. However, this does
not necessarily make the system perform better because the OS bypasses the
BIOS and uses the graphics driver to access the video card's hardware directly.
As such, it would be a waste of L2 cache bandwidth to cache the video BIOS
instead of data that are more critical to the system's performance. In addition, if
any program writes into this memory area, it will result in a system crash. So, it
is recommended that you write protect this area for optimal system performance.
Uncached / Write Protect
Cache Base 0-512K
This feature allows you to control caching of 512K base memory.
Uncached / Write Through / Write Protect / Write Back
Cache Base 512K-640K
This feature allows you to control caching of 512K 640K base memory.
Uncached / Write Through / Write Protect / Write Back
Cache Extended Memory Area
This feature allows you to control caching of system memory above one megabyte.
Uncached / Write Through / Write Protect / Write Back
Cache A000-AFFF/B000-BFFF
These features allow you to control caching of A000-AFFF/B000-BFFF memory.
Disabled / USMC Caching / Write Through / Write Protect / Write Back
Cahe C8000-CBFF/Cache CC00-CFFF
These features allow you to control caching of C8000-CBFF/CC00-CFFF memory.
Disabled / Write Through / Write Protect / Write Back
Cahe D000-D3FF/Cahe D400-D7FF/Cache D800-DBFF/Cahe DC00-DFFF
These features allow you to control caching of D000-D3FF/D400-D7FF/D800-
D8FF/DC00-DFFF memory.
Disabled / Write Through / Write Protect / Write Back
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