216
Recommended BIOS Settings
Chapter 7
AMD-761™ System Controller Software/BIOS Design Guide
24081D—February 2002
Preliminary Information
Registers
-----
Bits
Description
Initialized/
Required
Value
Actual
Value
Key
fcn( )
Notes
0x0x0x4Ch
PCI Control
31:04
Reserved
0000h
r
4:3
Reserved
00b
B
Must be set by BIOS
2
PCI_DT_En
0b
B
0= Disable Delayed
Transactions
1= Enable Delayed
Transactions
1
PCI_OR_EN
0b
B
0= Disable Ordering Rules
Compliance
1 = Enable PCI Ordering
Rules Compliance
0
Func1_En
0b
B
1= Enable 0x0x1xRR Access
0x0x0x50h
AMD Athlon™ System Bus
Dynamic Compensation
31:24
Reserved
00h
r
23:20
PVal
yh
c
P Transistor Value in Use
19:16
NVal
yh
c
N Transistor Value in Use
15:12
Byp_P
0h
B
P Transistor Value Used if
Byp = 1
11:8
Byp_N
0h
B
N Transistor Value Used if
Byp = 1
7:5
SlewCntl
011b
B
4
Byp
0b
B
1 = Enable Byp_P and Byp_N
3:0
Reserved
0h
r
KEY:
B= Mandatory BIOS function
A= AGP setup by BIOS
c = Calculated/set by AMD-761™ internal logic
P= Power management setup by BIOS
o = Setup by OS or OS driver
F = Performance enhancement set by BIOS
r = Hardcoded and reserved
u = PCI operational user interface
E = Elective BIOS function