Fine-Tuning the BIOS for the MS-A2 Home Lab

In my previous post I talked about moving my home lab onto the MS-A2 MiniPCs. This follow-up digs into the BIOS configuration I ended up with.

By default, the PC boots with stock settings, but for a VMware Cloud Foundation / ESX lab, you get the best experience if you spend 5 minutes tuning the BIOS.

These settings are based on the MS-A2 BIOS and ESX/ESXi builds I was testing at the time. Treat them as lab-proven defaults for this hardware, not a vendor support matrix.


BIOS Settings Summary

Menu PathDefault ValueChanged ValueJustification
Advanced -> Trusted Computing -> Security Device SupportEnabledDisabledTPM on a MS-A2 does not work on ESX
Advanced -> CPU Configuration ->PSS SupportEnabledLeave on; required for power states
Advanced -> CPU Configuration -> NX ModeEnabledNeeded for hypervisors, security
Advanced -> Onboard Devices -> NVMe RAID modeDisabledRAID not used in this setup
Advanced -> Onboard Devices -> PCIe Port -> WiFiEnabledDisabledWiFi unused in lab; frees PCIe resources
Advanced -> PCI SR-IOVDisabledEnabledRequired for vSphere SR-IOV NIC functions
Advanced -> Driver Health StatusDisabledEnabledBetter diagnostics if something fails POST
Advanced -> ACPI -> Wake Up on LANEnabledLeave on to allow remote wake. Closest there is for an OOB power on option
Advanced -> ACPI -> Wake Up by RTCDisabledNo need for scheduled RTC power-ons
Advanced -> ACPI -> PowerLimit SettingBalance ModePerformance ModeLab always on, so max performance
Advanced -> ACPI -> ERPDisabledKeeps USB ports powered when off. Had no reason to change this
Advanced -> Hardware Monitor -> Fan ModeAutoPerformanceKeeps airflow up under sustained load
Advanced -> Hardware Monitor -> CPU/System/SSD Fan SettingsAutoFans managed by board; left untouched
Advanced -> Network Stack -> Network StackDisabledEnabledRequired for PXE boot lab deployments.
Details are in my PXE booting post and the published PXE framework.
Advanced -> Network Stack -> IPv4 PXE SupportDisabledEnabledPXE for imaging/boot
Advanced -> Network Stack -> IPv6 PXE SupportDisabledIPv6 PXE not required in my lab
Advanced -> AMD PBS -> Primary Video AdaptorExt Graphics (PEG)Int Graphics (IGD)No GPU card; use iGPU
Advanced -> AMD PBS -> Special Display FeaturesHybridGraphicsDisabledPrevents unwanted muxing overhead
Advanced -> AMD PBS -> PCIe/GFW Lanes Configx8The Intel X710’s in the management hosts are x8 PCIe devices
Advanced -> AMD PBS -> GFX Lane SpeedGEN4AutoAvoids link training instability
Advanced → AMD PBS → SSD0 Lane SpeedAutoGEN3Iterated settings until stable ESXi NVMe detection
Advanced -> AMD PBS -> SSD1 Lane SpeedGEN3GEN4SSD1 NVMe slot I’m using for NVMe Tiering. Maximum performance required
Advanced -> AMD PBS -> SSD2 Lane SpeedGEN3GEN4SSD2 used for vSAN ESA. Matches capability of Samsung NVMe 990 PRO 4TB device
Advanced -> AMD CBS -> Core Performance BoostAutoLeave CPU boost logic on
Advanced -> AMD CBS -> Global C-state ControlAutoKeeps low-power states enabled
Advanced -> AMD CBS -> SVM LockAutoEnabledRequired for nested virtualization
Advanced -> AMD CBS -> SVM EnableAutoEnabledRequired for hypervisors
Advanced -> AMD CBS -> IOMMUAutoEnabledNeeded for PCI passthrough
Advanced -> AMD CBS -> GFX Config -> UMA Frame Buffer Size2G1GSave RAM for workloads
Advanced -> AMD CBS -> Audio Config → NB AzaliaEnabledDisabledNo onboard audio needed
Advanced -> AMD CBS -> AC Power Loss -> AC Loss ControlAlways OffAlways OnEnsures lab powers back on after outage
Advanced -> AMD CBS -> SMU OptionsAutoNo tweaks needed
Advanced -> AMD OverclockingUntouchedStability beats performance tuning
Advanced -> Addons -> X710 -> Wake On LANEnabledAllows out-of-band wake
Advanced -> Addons -> X710 -> Legacy VLAN ID0Default VLAN fine since I use native VLAN for PXE imaging
Advanced -> Addons -> X710 -> LLDP AgentEnabledDisabledAllows LLDP packets to pass to ESX
Security -> Administrator PasswordNot InstalledSet later for security, optional in lab
Secure Boot -> Secure BootEnabledDisabledDisabled as a lab convenience while testing install media and PXE flow. ESXi supports Secure Boot in supported configurations
Secure Boot v ModeStandardLeft untouched after disabling SB
Boot -> Quiet BootTickedUntickedI prefer seeing POST details

The Lowdown…

  • Virtualization features (SVM, IOMMU, SR-IOV) should be on for virtualization features.
  • Noise vs performance. My MS-A2’s are in a rack in an air-conditioned room so noise is not an issue. However wear your AirPods if they’re going to be in the same room as you work as the background noise may annoy some folks.
  • Networking/PXE configuration will allow PXE boot imaging of hosts.
  • Secure Boot/TPM disabled since MS-A2’s TPM doesn’t function in ESX.

This BIOS tuning has made the MS-A2 units pretty solid for my VMware lab. The temperatures of the NVMe devices range from 59C-72C depending on load.