TYAN S5221 User Manual page 36

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
Cache E000-E3FF/Cache E400-E7FF / Cache E8000-EBFF / Cache
EC00-EFFF
These features allow you to control caching of C8000-CBFF/CC00-
CFFF/Cache E8000-EBFF / Cache EC00-EFFF memory.
Disabled / Write Through / Write Protect / Write Back
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