GVC IN5598, Руководство пользователя

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4. BIOS SETUP
OS select for DRAM > 64MB
Select “ OS2 ” only if you are running OS/2 operating system with greater than 64 MB
of RAM on your system.
Shadow
This is software that resides in a Read-Only Memory, (ROM), chip on a device is
called “firmware”. The Award BIOS permits “
shadowing ” of firmware such as the
system BIOS, video BIOS, and similar operating instructions that come with some
expansion peripherals, such as, for example, a SCSI adaptor.
Shadowing copies firmware from ROM into system RAM, where the CPU can read it
through the 16-bit or 32-bit DRAM bus. Firmware not shadowed must be read by the
system through the 8-bit X-bus. Shadowing improves the performance of the system
BIOS and similar ROM firmware for expansion peripherals, but it also reduces the
amount of high memory (640 KB to 1 MB) available for loading device drivers, etc.
“ Enable ” shadowing into each section of memory separately. Many system designers
hard-wire shadowing of the system BIOS and eliminate a System BIOS Shadow option.
Video BIOS shadows into memory area C0000-C7FFF. The remaining areas shown on
the BIOS Features Setup screen may be occupied by other expansion card firmware. If
an expansion peripheral in your system contains ROM-based firmware, you need to
know the address range the ROM occupies to shadow it into the correct area of RAM.