i9 BIOS
Leo-Patch 1.6 · Q1HY MoDT · Observations 14 October 2026

PCIe and Graphics

PCI Express Root Port 21

PCI Express Root Port 21 firmware setup page decoded from AMI HII/IFR resources.

Form ID
0x13f8
Records
34
Path
Setup / Chipset / PCH-IO Configuration / PCI Express Configuration / PCI Express Root Port 21

Record 3956

PCI Express Root Port 21

Firmware Value

Control the PCI Express Root Port.

Opcode
OneOf
Question ID
0xe7b
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x113
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Record 3957

Connection Type

Firmware Value

Built-In: a built-in device is connected to this rootport.

Firmware help text

Built-In: a built-in device is connected to this rootport. SlotImplemented bit will be clear. Slot: this rootport connects to user-accessible slot. SlotImplemented bit will be set.

Opcode
OneOf
Question ID
0xe7c
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x37b
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Built-in
1SlotStandard default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1628, "type": "GrayOutIf", "offset": 500991, "expr": ["EqIdVal QuestionId: 0xE89, Value: 0x1"]}

Record 3958

ASPM

Firmware Value

Set the ASPM Level: Force L0s - Force all links to L0s State AUTO - BIOS auto configure DISABLE - Disables ASPM

Firmware help text

Set the ASPM Level: Force L0s - Force all links to L0s State AUTO - BIOS auto configure DISABLE - Disables ASPM

Opcode
OneOf
Question ID
0x15f4
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x12f
Width
1 byte(s)
Range
0 to 4 step 0
ValueLabelMarkers
0DisabledStandard default
2L1
4Auto

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3959

L1 Substates

Firmware Value

PCI Express L1 Substates settings.

Opcode
OneOf
Question ID
0x1610
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x2d3
Width
1 byte(s)
Range
0 to 2 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1L1.1
2L1.1 & L1.2

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3960

L1 Low

Firmware Value

PCI Express L1 Low Substate Enable/Disable.

Opcode
OneOf
Question ID
0xe7d
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x2ef
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3961

ACS

Firmware Value

Enable/Disable Access Control Services Extended Capability

Opcode
OneOf
Question ID
0xe7e
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x30b
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3962

PTM

Firmware Value

Enable/Disable Precision Time Measurement

Opcode
OneOf
Question ID
0x162c
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x327
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3963

DPC

Firmware Value

Enable/Disable Downstream Port Containment

Opcode
OneOf
Question ID
0xe7f
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x343
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3964

EDPC

Firmware Value

Enable/Disable Rootport extensions for Downstream Port Containment

Opcode
OneOf
Question ID
0xe80
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x35f
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3965

URR

Firmware Value

PCI Express Unsupported Request Reporting Enable/Disable.

Opcode
OneOf
Question ID
0xe81
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x14b
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3966

FER

Firmware Value

PCI Express Device Fatal Error Reporting Enable/Disable.

Opcode
OneOf
Question ID
0xe82
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x167
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3967

NFER

Firmware Value

PCI Express Device Non-Fatal Error Reporting Enable/Disable.

Opcode
OneOf
Question ID
0xe83
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x183
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3968

CER

Firmware Value

PCI Express Device Correctable Error Reporting Enable/Disable.

Opcode
OneOf
Question ID
0xe84
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x19f
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3969

SEFE

Firmware Value

Root PCI Express System Error on Fatal Error Enable/Disable.

Opcode
OneOf
Question ID
0xe85
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x1f3
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3970

SENFE

Firmware Value

Root PCI Express System Error on Non-Fatal Error Enable/Disable.

Opcode
OneOf
Question ID
0xe86
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x20f
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3971

SECE

Firmware Value

Root PCI Express System Error on Correctable Error Enable/Disable.

Opcode
OneOf
Question ID
0xe87
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x22b
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3972

PME SCI

Firmware Value

PCI Express PME SCI Enable/Disable.

Opcode
OneOf
Question ID
0xe88
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x247
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3973

Hot Plug

Firmware Value

PCI Express Hot Plug Enable/Disable.

Opcode
OneOf
Question ID
0xe89
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x263
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1629, "type": "GrayOutIf", "offset": 501543, "expr": ["EqIdVal QuestionId: 0xE7C, Value: 0x0"]}

Record 3974

Advanced Error Reporting

Firmware Value

Advanced Error Reporting Enable/Disable.

Opcode
OneOf
Question ID
0xe8a
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x27f
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3975

PCIe Speed

Firmware Value

Configure PCIe Speed

Opcode
OneOf
Question ID
0xe8b
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x29b
Width
1 byte(s)
Range
0 to 3 step 0
ValueLabelMarkers
0AutoStandard default
1Gen1
2Gen2
3Gen3

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3976

Transmitter Half Swing

Firmware Value

Transmitter Half Swing Enable/Disable.

Opcode
OneOf
Question ID
0xe8c
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x2b7
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3977

Detect Timeout

Firmware Value

The number of milliseconds reference code will wait for link to exit Detect state for enabled ports before assuming there is no device and potentially disabling the port.

Opcode
Numeric
Question ID
0xe8d
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x3ab
Width
2 byte(s)
Range
0 to 65535 step 1

Default store records

Store IDStore labelValueOption label
0Standard0

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3978

Extra Bus Reserved

Firmware Value

Extra Bus Reserved (0-7) for bridges behind this Root Bridge.

Opcode
Numeric
Question ID
0xe8e
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x533
Width
1 byte(s)
Range
0 to 7 step 1

Default store records

Store IDStore labelValueOption label
0Standard0

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3979

Reserved Memory

Firmware Value

Reserved Memory for this Root Bridge (1-20) MB

Opcode
Numeric
Question ID
0xe8f
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x563
Width
2 byte(s)
Range
1 to 20 step 1

Default store records

Store IDStore labelValueOption label
0Standard10

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3980

Reserved I/O

Firmware Value

Reserved I/O (4K/8K/12K/16K/20K) Range for this Root Bridge.

Opcode
Numeric
Question ID
0xe90
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x587
Width
1 byte(s)
Range
4 to 20 step 4

Default store records

Store IDStore labelValueOption label
0Standard4

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3981

LTR

Firmware Value

PCH PCIE Latency Reporting Enable/Disable

Opcode
OneOf
Question ID
0xe91
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x3f7
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0Disabled
1EnabledStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3982

Snoop Latency Override

Firmware Value

Snoop Latency Override for PCH PCIE.

Firmware help text

Snoop Latency Override for PCH PCIE. Disabled: Disable override. Manual: Manually enter override values. Auto (default): Maintain default BIOS flow.

Opcode
OneOf
Question ID
0xe92
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x42f
Width
1 byte(s)
Range
0 to 2 step 0
ValueLabelMarkers
0Disabled
1Manual
2AutoStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1630, "type": "SuppressIf", "offset": 501858, "expr": ["EqIdVal QuestionId: 0xE91, Value: 0x0"]}

Record 3983

Snoop Latency Value

Firmware Value

LTR Snoop Latency value of PCH PCIE

Opcode
Numeric
Question ID
0xe93
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x4b3
Width
2 byte(s)
Range
0 to 1023 step 1

Default store records

Store IDStore labelValueOption label
0Standard60

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1630, "type": "SuppressIf", "offset": 501858, "expr": ["EqIdVal QuestionId: 0xE91, Value: 0x0"]}
  • {"condition_id": 1631, "type": "SuppressIf", "offset": 501906, "expr": ["EqIdVal QuestionId: 0xE92, Value: 0x1", "Not"]}

Record 3984

Snoop Latency Multiplier

Firmware Value

LTR Snoop Latency Multiplier of PCH PCIE

Opcode
OneOf
Question ID
0xe94
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x44b
Width
1 byte(s)
Range
0 to 5 step 0
ValueLabelMarkers
01 ns
132 ns
21024 nsStandard defaultManufacturing default
332768 ns
41048576 ns
533554432 ns

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1630, "type": "SuppressIf", "offset": 501858, "expr": ["EqIdVal QuestionId: 0xE91, Value: 0x0"]}
  • {"condition_id": 1631, "type": "SuppressIf", "offset": 501906, "expr": ["EqIdVal QuestionId: 0xE92, Value: 0x1", "Not"]}

Record 3985

Non Snoop Latency Override

Firmware Value

Non Snoop Latency Override for PCH PCIE.

Firmware help text

Non Snoop Latency Override for PCH PCIE. Disabled: Disable override. Manual: Manually enter override values. Auto (default): Maintain default BIOS flow.

Opcode
OneOf
Question ID
0xe95
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x467
Width
1 byte(s)
Range
0 to 2 step 0
ValueLabelMarkers
0Disabled
1Manual
2AutoStandard defaultManufacturing default

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1630, "type": "SuppressIf", "offset": 501858, "expr": ["EqIdVal QuestionId: 0xE91, Value: 0x0"]}

Record 3986

Non Snoop Latency Value

Firmware Value

LTR Non Snoop Latency value of PCH PCIE

Opcode
Numeric
Question ID
0xe96
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x4eb
Width
2 byte(s)
Range
0 to 1023 step 1

Default store records

Store IDStore labelValueOption label
0Standard60

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1630, "type": "SuppressIf", "offset": 501858, "expr": ["EqIdVal QuestionId: 0xE91, Value: 0x0"]}
  • {"condition_id": 1632, "type": "SuppressIf", "offset": 502050, "expr": ["EqIdVal QuestionId: 0xE95, Value: 0x1", "Not"]}

Record 3987

Non Snoop Latency Multiplier

Firmware Value

LTR Non Snoop Latency Multiplier of PCH PCIE

Opcode
OneOf
Question ID
0xe97
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x483
Width
1 byte(s)
Range
0 to 5 step 0
ValueLabelMarkers
01 ns
132 ns
21024 nsStandard defaultManufacturing default
332768 ns
41048576 ns
533554432 ns

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}
  • {"condition_id": 1630, "type": "SuppressIf", "offset": 501858, "expr": ["EqIdVal QuestionId: 0xE91, Value: 0x0"]}
  • {"condition_id": 1632, "type": "SuppressIf", "offset": 502050, "expr": ["EqIdVal QuestionId: 0xE95, Value: 0x1", "Not"]}

Record 3988

LTR Lock

Firmware Value

PCIE LTR Configuration Lock

Opcode
OneOf
Question ID
0xe98
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0x413
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}

Record 3989

Peer Memory Write Enable

Firmware Value

Peer Memory Write Enable/Disable

Opcode
OneOf
Question ID
0xe99
VarStore
PchSetup
VarStore GUID
4570B7F1-ADE8-4943-8DC3-406472842384
Offset
0xd2
Width
1 byte(s)
Range
0 to 1 step 0
ValueLabelMarkers
0DisabledStandard defaultManufacturing default
1Enabled

Visibility / conditions

  • {"condition_id": 1627, "type": "SuppressIf", "offset": 500983, "expr": ["EqIdVal QuestionId: 0xE7B, Value: 0x0"]}