Abit AX5 Instruction Booklet page 61

Introduction of BIOS
Attention:Unless you are very familiar with your computer and with the
DRAM configuration and speed, we recommend you not
change the DRAM options but enable this option.
DRAM settings:
The other DRAM settings are all closely related to hardware. If you do not
understand this very well, don' t make any changes. Our BIOS is able to
autodetect the characteristics of your DRAM and to choose the best
settings.
Memory Hole At 15M-16M:
This option is used to free up the 15M-16M memory block. Some special
peripherals need to use a memory bloc located between 15M and 16M, and
this memory block has a size of 1M. We recommend that you disable this
option.
There are small differences in the chipset feature setup according to
different mainboard models, but this has no influence upon performance. Our
default setup should be the best one. That is the reason why we do not describe
all the features of this menu.
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