CHAINTECH 6VIA6, Руководство пользователя

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Award BIOS Setup Program
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E. Security Option
The Supervisor and/or User Password functions shown in Figure 3-1 must be set
to take advantage of this function. See Section 3-11 for password setting
information. When the Security Option is set to System, a password must be
entered to boot the system or enter the BIOS setup program. When the Security
Option is set to Setup, a password is required to enter the BIOS setup program.
F. OS Select (For DRAM >64MB)
If your system's DRAM is larger than 64MB and you are running OS/2 , select
OS/2 as the item value. Otherwise, set the item value to Non-OS/2 for all other
operating systems.
G. Shadow Memory
Software such as system BIOS, video BIOS, SCSI BIOS, etc. that resides in ROM
(Read Only Memory) chips is called firmware. Shadowing of firmware occurs
when BIOS is copied to RAM address C0000h through DFFFFh. Video BIOS
loads into the C0000-C7FFF memory area when video shadowing is enabled.
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.
Shadowing improves the firmware's performance because the firmware can be read
by the CPU through the 16- or 32-bit DRAM bus as opposed to the 8-bit XT
bus. However, shadowing also results in reducing the amount of high memory
(640 KB to 1 MB) for loading device drivers. Shadowing is used mostly for
ROM chips on ISA cards and not for PCI cards. Shadowing and playing games
at the same time may result in system instability as some games access the RAM
memory area being shadowed.