BIOS Manual Motherboard PRIME/Pro/ ProArt/TUF GAMING B550/A520 Series
E16863 First Edition June 2020 Copyright© 2020 ASUSTeK COMPUTER INC. All Rights Reserved. No part of this manual, including the products and software described in it, may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language in any form or by any means, except documentation kept by the purchaser for backup purposes, without the express written permission of ASUSTeK COMPUTER INC. (“ASUS”).
Contents 1.1 1.2 Knowing BIOS................................................................................................ 4 BIOS setup program...................................................................................... 5 1.2.1 EZ Mode......................................................................................... 6 1.2.2 Advanced Mode.............................................................................. 7 1.2.3 QFan Control................................................
BIOS Setup 1.1 Knowing BIOS The new ASUS UEFI BIOS is a Unified Extensible Interface that complies with UEFI architecture, offering a user-friendly interface that goes beyond the traditional keyboardonly BIOS controls to enable a more flexible and convenient mouse input. You can easily navigate the new UEFI BIOS with the same smoothness as your operating system. The term “BIOS” in this user manual refers to “UEFI BIOS” unless otherwise specified.
1.2 BIOS setup program Use the BIOS Setup to update the BIOS or configure its parameters. The BIOS screens include navigation keys and brief onscreen help to guide you in using the BIOS Setup program. Entering BIOS at startup To enter BIOS Setup at startup, press or during the Power-On Self Test (POST). If you do not press or , POST continues with its routines. Entering BIOS Setup after POST To enter BIOS Setup after POST: • Press ++ simultaneously.
1.2.1 EZ Mode The EZ Mode provides you an overview of the basic system information, and allows you to select the display language, system performance, mode and boot device priority. To access the Advanced Mode, select Advanced Mode or press the hotkey for the advanced BIOS settings. The default screen for entering the BIOS setup program can be changed. Refer to the Setup Mode item in section Boot menu for details. Displays the CPU/motherboard Displays the system properties of the selected mode.
1.2.2 Advanced Mode The Advanced Mode provides advanced options for experienced end-users to configure the BIOS settings. The figure below shows an example of the Advanced Mode. Refer to the following sections for the detailed configurations. To switch from EZ Mode to Advanced Mode, click Advanced Mode(F7) or press the hotkey.
Menu bar The menu bar on top of the screen has the following main items: My Favorites For saving the frequently-used system settings and configuration. Main For changing the basic system configuration Ai Tweaker For changing the overclocking settings Advanced For changing the advanced system settings Monitor For displaying the system temperature, power status, and changing the fan settings.
AURA ON/OFF(F4) This button allows you to turn the RGB LED lighting or functional LED on or off. [All On]: All LEDs (Aura or Functional) will be enabled. [Aura Only]: Aura LEDs will be enabled and functional LEDs will be disabled. [Aura Off]: Aura LEDs will be disabled, however functional LEDs will still be enabled. [Stealth Mode]: All LEDs (Aura and Functional) will be disabled. Hot keys This button above the menu bar contains the navigation keys for the BIOS setup program.
1.2.3 QFan Control The QFan Control allows you to set a fan profile or manually configure the operating speed of your CPU and chassis fans.
Configuring fans manually Select Manual from the list of profiles to manually configure your fans’ operating speed. Speed points Select to manually configure your fans To configure your fans: 1. Select the fan that you want to configure and to view its current status. 2. Click and drag the speed points to adjust the fans’ operating speed. 3. Click Apply to save the changes then click Exit (ESC).
1.3 My Favorites My Favorites is your personal space where you can easily save and access your favorite BIOS items. You can personalize this screen by adding or removing items.
Adding items to My Favorites To add BIOS items: 1. Press on your keyboard or click MyFavorites(F3) from the BIOS screen to open Setup Tree Map screen. 2. On the Setup Tree Map screen, select the BIOS items that you want to save in My Favorites screen. Main menu panel Selected shortcut items Submenu panel Delete all favorite items Recover to default favorite items 3.
1.4 Main menu The Main menu screen appears when you enter the Advanced Mode of the BIOS Setup program. The Main menu provides you an overview of the basic system information, and allows you to set the system date, time, language, and security settings. Security The Security menu items allow you to change the system security settings. 14 • If you have forgotten your BIOS password, erase the CMOS Real Time Clock (RTC) RAM to clear the BIOS password.
Administrator Password If you have set an administrator password, we recommend that you enter the administrator password for accessing the system. Otherwise, you might be able to see or change only selected fields in the BIOS setup program. To set an administrator password: 1. Select the Administrator Password item and press . 2. From the Create New Password box, key in a password, then press . 3. Re-type to confirm the password then select OK. To change an administrator password: 1.
1.5 Ai Tweaker menu The Ai Tweaker menu items allow you to configure overclocking-related items. Be cautious when changing the settings of the Ai Tweaker menu items. Incorrect field values can cause the system to malfunction. The configuration options for this section vary depending on the motherboard model,as well as the CPU and DIMM model you installed on the motherboard. Scroll down to display other BIOS items.
Memory Frequency This item allows you to set the memory operating frequency. The configurable options vary with the BCLK (base clock) frequency setting. Select the auto mode to apply the optimized setting. Configuration options: [Auto] [DDR4-1333MHz] – [DDR4-6000MHz] Selecting a very high memory frequency may cause the system to become unstable! If this happens, revert to the default setting. FCLK Frequency This item allows you to specify the FCLK frequency.
Max CPU Boost Clock Override This item allows you to increase the maximum CPU frequency that may be automatically achieved by the Precision Boost 2 algorithm. Configuration options: [Auto] [0MHz] [25MHz] [75MHz] [100MHz] [125MHz] [150MHz] [175MHz] [200MHz] Platform Thermal Throttle Limit This item allows you to decrease the maximum allowed processor temperature (celsius).Configuration options: [Auto] [Manual] DRAM Timing Control The sub-items in this menu allow you to set the DRAM timing control features.
TrdrdScl Configuration options: [Auto] [1] – [15] TwrwrScl Configuration options: [Auto] [1] – [63] Trfc Configuration options: [Auto] [60] – [1023] Trfc2 Configuration options: [Auto] [60] – [1023] Trfc4 Configuration options: [Auto] [60] – [990] Tcwl Configuration options: [Auto] [9] – [22] Trtp Configuration options: [Auto] [5] – [14] Trdwr Configuration options: [Auto] [1] – [31] Twrrd Configuration options: [Auto] [1] – [15] TwrwrSc Configuration options: [Auto] [1] – [15] TwrwrSd Configuration options
Gear Down Mode Configuration options: [Auto] [Enabled] [Disabled] Power Down Enable Configuration options: [Auto] [Enabled] [Disabled] RttNom Configuration options: [Auto] [Rtt_Nom Disable] [RZQ/4] [RZQ/2] [RZQ/6] [RZQ/1] [RZQ/5] [RZQ/3] [RZQ/7] RttWr Configuration options: [Auto] [Dynamic ODT Off] [RZQ/2] [RZQ/1] [Hi-Z] [RZQ/3] RttPark Configuration options: [Auto] [Rtt_PARK Disable] [RZQ/4] [RZQ/2] [RZQ/6] [RZQ/1] [RZQ/5] [RZQ/3] [RZQ/7] MemAddrCmdSetup Configuration options: [Auto] [0]-[63] MemCsOdtSetup
DIGI+ VRM Changing the values in this menu may cause the system to become unstable! If this happens, revert to the default settings. VDDCR CPU Load Line Calibration Load-line affects CPU power voltage. The CPU working voltage decreases proportionally to CPU loading. Higher load-line calibration could get higher voltage and good overclocking performance, but increases the CPU and VRM thermal conditions. Select from levels 1 to 5 to adjust the load-line slope.
VDDCR CPU Power Duty Control This item allows you to set the duty cycle of each VRM phase based upon current and/ or temperature. [T.Probe] Sets the buck controller to balance VRM FET temperatures. [Extreme] Sets the buck controller to balance per phase current. DO NOT remove the thermal module. The thermal conditions should be monitored.
VDDCR SOC Voltage Override Configuration options: [Auto] [0.750] - [2.000] The following items appear only when you set the VDDCR SOC Voltage to [Offset mode]. VDDCR SOC Offset Mode Sign [+] To offset the voltage by a positive value. [–] To offset the voltage by a negative value. VDDCR SOC Offset Voltage Configuration options: [Auto] [-0.00625] - [+0.50000] DRAM Voltage Configuration options: [Auto] [1.20] – [1.80] VDDG CCD Voltage Control Configuration options: [Auto] [0.700] – [1.
1.6 Advanced menu The Advanced menu items allow you to change the settings for the CPU and other system devices. Be cautious when changing the settings of the Advanced menu items. Incorrect field values can cause the system to malfunction.
1.6.1 AMD fTPM configuration The items in this menu show the AMD fTPM configuration options. TPM Device Selection This item allows you to select the TPM device. Configuration options: [Discrete TPM] [Firmware TPM] When Firmware TPM is set to disabled all saved data on it will be lost. Erase fTPM NV for factory reset This item allows you to enable or disable fTPM reset for newly installed CPUs.
1.6.2 CPU Configuration The items in this menu show the CPU-related information that the BIOS automatically detects. The items in this menu may vary based on the CPU installed. PSS Support This item allows you enable or disable the generation of ACPI_PPC, _PSS, and _PCT objects. Configuration options: [Disabled] [Enabled] NX Mode This item allows you enable or disable No-execute page protection function.
1.6.3 SATA Configuration While entering Setup, the BIOS automatically detects the presence of SATA devices. The SATA Port items show Not Present if no SATA device is installed to the corresponding SATA port. SATA Port Enable This item allows you to enable or disable the SATA Device. Configuration options: [Disabled] [Enabled] SATA Mode This item allows you to set the SATA configuration. [AHCI] Set to [AHCI] when you want the SATA hard disk drives to use the AHCI (Advanced Host Controller Interface).
SATA6G_1(Gray) - SATA6G_6(Gray) SATA6G_1 - SATA6G_6 This item allows you to enable or disable the selected SATA port. Configuration options: [Disabled] [Enabled] The number of the SATA ports varies by motherboard models. Hot Plug These items appears only when the SATA Mode is set to [AHCI] and allows you to enable or disable SATA Hot Plug Support. Configuration options: [Disabled] [Enabled] M.2_1(Gray) - M.2_2(Gray) M.2_1 - M.2_2 This item allows you to rename the AMD M.2 slots. The number of the M.
PCIEX16_1 Mode This item allows you to select the link speed for PCIEX16_1 slot. Configuration options: [Auto] [Gen 1] [Gen 2] [Gen 3] [Gen 4] M.2_1 Link Mode This item allows you to select the link speed for M.2_1 slot. Configuration options: [Auto] [Gen 1] [Gen 2] [Gen 3] [Gen 4] SB Link Mode This item allows you to select the link speed for Southbridge. Configuration options: [Auto] [Gen 1] [Gen 2] [Gen 3] PCIEX1 Mode This item allows you to select the link speed for PCIEX1 slot.
2.5G LAN Controller availability varies by motherboard models. Realtek PXE OPROM This item allows you to enable or disable Realtek PXE OPROM launch. Configuration options: [On] [Off] Wi-Fi Controller This item allows you to enable or disable the Wi-Fi controller. Configuration options: [Disabled] [Enabled] Wi-Fi Controller availability varies by motherboard models. Bluetooth Controller This item allows you to enable or disable the Bluetooth controller.
1.6.5 APM Configuration The items in this menu allow you to set system wake and sleep settings. ErP Ready This item allows you to switch off some power at S4+S5 or S5 to get the system ready for ErP requirement. When set to [Enabled], all other PME options are switched off. Configuration options: [Disabled] [Enable(S4+S5)] [Enable(S5)] Energy Star Ready This item allows you to enable or disable Energy Star.
1.6.6 PCI Subsystem Settings The items in this menu allow you to set PCI, PCI-X, and PCI Express settings. SR-IOV Support This option enables or disables Single Root IO Virtualization Support if the system has SRIOV capable PCIe devices. Configuration options: [Disabled] [Enabled] 1.6.7 USB Configuration The items in this menu allow you to change the USB-related features. Legacy USB Support [Enabled] Your system supports the USB devices in legacy operating systems.
USB Single Port Control This item allows you to enable or disable the individual USB ports. Refer to section Motherboard layout in your motherboard user manual for the location of the USB ports. 1.6.8 Network Stack Configuration The items in this menu allow you to enable or disable the UEFI network stack Network stack This item allows you to disable or enable the UEFI network stack. Configuration options: [Disable] [Enable] The following item appears only when you set Network Stack to [Enabled].
1.6.10 NVMe Configuration This menu displays the NVMe controller and Drive information of the connected devices. 1.6.11 AMD CBS The items in this menu shows the AMD Common BIOS Specifications.
IOMMU Configuration options: [Auto] [Disabled] [Enabled] PCIe ARI Support Configuration options: [Auto] [Disabled] [Enabled] PCIe Ten Bit Tag Support Configuration options: [Auto] [Disabled] [Enabled] 1.6.12 AMD PBS The items in this menu shows the AMD PBS Setup Page. Thunderbolt Support This option allows you to enable or disable Thunderbolt support. Configuration options: [Disabled] [Enabled] The following items appear only when you set Thunderbolt Support to [Enabled].
Legacy/Native/RTD3 This item allows you to select the Thunderbolt legacy/native/RTD3 mode. Configuration options: [Legacy Mode] [Native Mode] [Native + RTD3Hot] [Native + RTD3Cold] Thunderbolt Wake Up Command This item allows you to select the Thunderbolt wake-up command. Configuration options: [Disabled] [GO2SX Command] [GO2SX_NO_WAKE Command] The following item appears depending on the CPU model you installed on the motherboard.
1.7 Monitor menu The Monitor menu displays the system temperature/power status, and allows you to change the fan settings. Scroll down to display the other BIOS items. CPU Temperature, CPU Package Temperature, MotherBoard Temperature, Chipset Temperature, T_Sensor Temperature [xxx°C/xxx°F] The onboard hardware monitor automatically detects and displays the CPU, CPU Package, motherboard, chipset and T_Sensor temperatures. Select [Ignore] if you do not wish to display the detected temperatures.
Q-fan Configuration Q-fan Tuning Click this item to automatically detect the lowest speed and configure the minimum duty cycle for each fan. CPU Q-Fan Control This item allows you to set the CPU Q-Fan operating mode. [Auto] Detects the type of CPU fan installed and automatically switches the control modes. [PWM Mode] Enables the CPU Q-Fan Control feature in PWM mode for 4-pin CPU fan. [DC Mode] Enables the CPU Q-Fan Control feature in DC mode for 3-pin CPU fan. [Disabled] Disables the Q-Fan Control.
CPU Middle Temperature Use the <+> and <-> keys to adjust the CPU middle temperature. CPU Fan Middle. Duty Cycle(%) Use the <+> or <-> keys to adjust the CPU fan middle duty cycle. CPU Lower Temperature Use the <+> or <-> keys to adjust the lower limit of the CPU temperature. The CPU fan will operate at the minimum duty cycle when the CPU temperature is lower than the limit. CPU Fan Min. Duty Cycle(%) Use the <+> and <-> keys to adjust the minimum CPU fan duty cycle.
Chassis Fan 1-3 Profile This item allows you to set the appropriate performance level of the chassis fan. [Standard] Sets to [Standard] to make the chassis fan automatically adjust depending on the chassis temperature. [Silent] Sets to [Silent] to minimize the fan speed for quiet chassis fan operation. [Turbo] Sets to [Turbo] to achieve maximum chassis fan speed. [Manual] Sets to [Manual] to assign detailed fan speed control parameters.
AIO PUMP Control [Disabled] Disable the AIO Pump control feature. [Auto] Detects the type of AIO Pump installed and automatically switches the control modes. [DC mode] Enable the AIO Pump control in DC mode for 3-pin chassis fan. [PWM mode] Enable the AIO Pump control in PWM mode for 4-pin chassis fan. The following items appear only when you set the AIO Pump Control to [Auto], [DC mode] or [PWM mode].
1.8 Boot menu The Boot menu items allow you to change the system boot options. Boot Configuration Fast Boot [Disabled] [Enabled] Allows your system to go back to its normal boot speed. Allows your system to accelerate the boot speed. The following items appear only when you set the Fast Boot to [Enabled]. Next Boot after AC Power Loss [Normal Boot] Returns to normal boot on the next boot after an AC power loss. [Fast Boot] Accelerates the boot speed on the next boot after an AC power loss.
Boot up NumLock State This item allows you to enable or disable power-on state of the NumLock. Configuration options: [On] [Off] Wait For ‘F1’ If Error This item allows your system to wait for the key to be pressed when error occurs. Configuration options: [Disabled] [Enabled] Option ROM Messages [Force BIOS] The third-party ROM messages will be forced to display during the boot sequence.
Boot from Storage Devices This item allows you to select the type of storage devices that you want to launch. Configuration options: [Ignore] [Legacy only] [UEFI driver first] [UEFI only] Boot from PCI-E/ PCI Expansion Devices This item allows you to select the type of PCI-E/ PCI expansion devices that you want to launch.
KEK Management The Key Exchange Keys (KEK) manages the Signature database (db) and Forbidden Signature database (dbx). Key Exchange Keys (KEK) refers to Microsoft® Secure Boot Key-Enrollment Key (KEK). Save to file This item allows you to save the KEK to a USB storage device. Set New key This item allows you to load the downloaded KEK from a USB storage device. Append Key This item allows you to load the additional KEK from a storage device for an additional db and dbx loaded management.
Set New key This item allows you to load the downloaded dbx from a USB storage device. Append Key This item allows you to load the additional dbx from a storage device for an additional db and dbx loaded management. Delete key This item allows you to delete the dbx file from your system. Configuration options: [Yes] [No] The dbx file must be formatted as a UEFI variable structure with time-based authenticated variable.
1.9 Tool menu The Tool menu items allow you to configure options for special functions. Select an item then press to display the submenu. 1.9.1 ASUS EZ Flash 3 Utility This item allows you to run ASUS EZ Flash 3. When you press , a confirmation message appears. Use the left/right arrow key to select between [Yes] or [No], then press to confirm your choice. For more details, refer to section 1.11.2 ASUS EZ Flash 3. 1.9.
Status definition: 1.9.3 • Frozen. The frozen state is the result of a BIOS protective measure. The BIOS guards drives that do not have password protection by freezing them prior to booting. If the drive is frozen, a power off or hard reset of your PC must be performed to proceed with the ASUS Secure Erase. • Locked. SSDs might be locked if the Secure Erase process is either incomplete or was stopped. This may be due to a third party software that uses a different password defined by ASUS.
1.10 Exit menu The Exit menu items allow you to load the optimal default values for the BIOS items, and save or discard your changes to the BIOS items. You can access the EZ Mode from the Exit menu. Load Optimized Defaults This option allows you to load the default values for each of the parameters on the Setup menus. When you select this option or if you press , a confirmation window appears. Select OK to load the default values.
1.11 Updating BIOS The ASUS website publishes the latest BIOS versions to provide enhancements on system stability, compatibility,and performance. However, BIOS updating is potentially risky. If there is no problem using the current version of BIOS, DO NOT manually update the BIOS. Inappropriate BIOS updating may result to system’s failure to boot. Carefully follow the instructions in this chapter to update your BIOS when necessary. Visit http://www.asus.
1.11.2 ASUS EZ Flash 3 The ASUS EZ Flash 3 feature allows you to update the BIOS without using an OS‑based utility. Ensure to load the BIOS default settings to ensure system compatibility and stability. Select the Load Optimized Defaults item under the Exit menu or press hotkey . To update the BIOS by USB: • This function can support devices such as a USB flash disk with FAT 32/16 format and single partition only.
1.11.3 ASUS CrashFree BIOS 3 The ASUS CrashFree BIOS 3 utility is an auto recovery tool that allows you to restore the BIOS file when it fails or gets corrupted during the updating process. You can restore a corrupted BIOS file using a USB flash drive that contains the BIOS file. If you want to use the latest BIOS file, download the file at https://www.asus.com/support/ and save it to a USB flash drive. Recovering the BIOS To recover the BIOS: 1. Turn on the system. 2.
