Intel ICH9 Information Manual page 21

ICH8/ICH9—NVM Information Guide
Bit
8
7:6
5
4:3
2
1:0
Name
Display Setup Message.
If this bit is set to 1b, the "Press Control-S" message appears after the
DSM
title message.
The default for this bit is 1b.
Prompt Time. These bits control how long the "Press Control-S" setup
prompt message appears, if enabled by DIM.
00b = 2 seconds (default)
01b = 3 seconds
PT
10b = 5 seconds
11b = 0 seconds
Note that the Ctrl-S message does not appear if 0 seconds prompt time
is selected.
Reserved Reserved
Default Boot Selection. These bits select which device is the default
boot device. These bits are only used if the agent detects that the BIOS
does not support boot order selection or if the MODE field of word 31h
is set to MODE_LEGACY.
DBS
00b = Network boot, then local boot
01b = Local boot, then network boot
10b = Network boot only
11b = Local boot only
Reserved Reserved
Protocol Select. These bits select the boot protocol.
00b = PXE (default value)
PS
01b = RPL protocol
Other values are undefined.
Description
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