• Dell Latitude 5591 ¹⁾
• 2024/06/01: BIOS 1.32
• 2024/09/25: Something (presumably PCI-related) causes iwlwifl to firmware-crash

• Enable/Disable Overclocking Lock (BIT 20) in FLEX_RATIO(194) MSR

• Default: Enabled 1
• Ideal: Disabled 0

setup_var_cv Setup 0x659 0x1 0x0

• Configure MSR 0xE2[15], CFG Lock bit

• Default: Enabled 1
• Ideal: Disabled 0

setup_var_cv Setup 0x5BD 0x1 0x0

• Select DVMT 5.0 Pre-Allocated (Fixed) Graphics Memory size used by the Internal Graphics Device

• Default: Unknown
• Ideal: 64M 2

setup_var_cv Setup 0x8D2 0x1 0x2

• Select DVMT5.0 Total Graphic Memory size used by the Internal Graphics Device

• Default: Unknown
• Ideal: MAX 3

setup_var_cv Setup 0x8D3 0x1 0x3

• Enable/Disable above 4GB MemoryMappedIO BIOS assignment
• This is enabled automatically when Aperture Size is set to 2048MB

• Default: Disabled 0
• Ideal: Enabled 1

setup_var_cv Setup 0x8D7 0x1 0x1

• Select the Aperture Size

• Default: 256MB 1
• Ideal: 2048MB 15

setup_var_cv Setup 0x821 0x1 0xF

• Enable PCH to aggressively enter link power state

• Default: Enabled 1
• Ideal: Disabled 0

setup_var_cv Setup 0xA7E 0x1 0x0

• Maximum Value of TOLUD
• Dynamic assignment would adjust TOLUD automatically based on largest MMIO length of installed graphic controller

• TODO: Check this for 1.33

• Default: Unknown

setup_var_cv Setup 0x90E 0x1 0x0

• Check to enable render standby support

• Default: Enabled 1
• Ideal: Disabled 0

setup_var_cv Setup 0x81B 0x1 0x0

• When a processor thermal sensor trips (either core), the PROCHOT# will be driven
• If bi-direction is enabled, external agents can drive PROCHOT# to throttle the processor

• Default: Enabled 1
• Ideal: Disabled 0

setup_var_cv Setup 0x5F4 0x1 0x0

• Select the LCD panel scaling option used by the Internal Graphics Device

• Default: Auto 0
• Ideal: Off 1

setup_var_cv Setup 0x81A 0x1 0x1

• Enable/Disable WatchDog Timer

• Default: Enabled 1
• Ideal: Disabled 0

setup_var_cv Setup 0x7D1 0x1 0x0

• The control of Active State Power Management of the DMI Link

• Default: Auto 4
• Ideal: Disabled 0

setup_var_cv Setup 0xEE6 0x1 0x0

• Enable/Disable the control of Active State Power Management on SA side of the DMI Link
• SA is System Agent?

• Default: L0sL1 3
• Ideal: Disabled 0

setup_var_cv Setup 0x900 0x1 0x0

• Set DMI Speed Gen1/Gen2/Gen3

• Default: Auto 0
• Ideal: Gen3 3

setup_var_cv Setup 0x8DE 0x1 0x3

• https://github.com/erpalma/throttled/issues/97
• https://github.com/mihic/linux-intel-undervolt
• https://github.com/erpalma/throttled/blob/master/throttled.py
• https://github.com/DivyanshuVerma/throttlestop-linux (prochot)

• ThrottleStop: FIVRVoltage00=0xF3200000
• -100.6 mV Offset Voltage

wrmsr --all '0x150' '80000011F3200000'

• ThrottleStop: IccMaxNew00=0x000003FF
• 255.75 A

wrmsr --all '0x150' '0x80000017000003ff'

• ThrottleStop: FIVRVoltage20=0xF3200000
• -100.6 mV Offset Voltage

wrmsr --all '0x150' '80000211F3200000'

• ThrottleStop: IccMaxNew20=0x000003FF
• 255.75 A

wrmsr --all '0x150' '0x80000217000003ff'

• ThrottleStop: FIVRVoltage40=0xF3200000
• -100.6 mV Offset Voltage

wrmsr --all '0x150' '80000411F3200000'

• ThrottleStop: IccMaxNew40=0x000003FF
• 255.75 A

wrmsr --all '0x150' '0x80000417000003ff'