diff --git a/ArmVirtPkg/ArmVirt.dsc.inc b/ArmVirtPkg/ArmVirt.dsc.inc
index 6c6a52b5e6..c624b3cdbe 100644
--- a/ArmVirtPkg/ArmVirt.dsc.inc
+++ b/ArmVirtPkg/ArmVirt.dsc.inc
@@ -67,9 +67,8 @@
   #
   PcdLib|MdePkg/Library/DxePcdLib/DxePcdLib.inf
 
-  # 1/123 faster than Stm or Vstm version
-  #BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
-  BaseMemoryLib|ArmPkg/Library/BaseMemoryLibStm/BaseMemoryLibStm.inf
+  # use the accelerated BaseMemoryLibOptDxe by default, overrides for SEC/PEI below
+  BaseMemoryLib|MdePkg/Library/BaseMemoryLibOptDxe/BaseMemoryLibOptDxe.inf
 
   # Networking Requirements
   NetLib|MdeModulePkg/Library/DxeNetLib/DxeNetLib.inf
@@ -154,6 +153,7 @@
 
 [LibraryClasses.common.SEC]
   PcdLib|MdePkg/Library/BasePcdLibNull/BasePcdLibNull.inf
+  BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
 
   DebugAgentLib|ArmPkg/Library/DebugAgentSymbolsBaseLib/DebugAgentSymbolsBaseLib.inf
   DefaultExceptionHandlerLib|ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLibBase.inf
@@ -165,6 +165,7 @@
 
 [LibraryClasses.common.PEI_CORE]
   PcdLib|MdePkg/Library/PeiPcdLib/PeiPcdLib.inf
+  BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
   HobLib|MdePkg/Library/PeiHobLib/PeiHobLib.inf
   PeiServicesLib|MdePkg/Library/PeiServicesLib/PeiServicesLib.inf
   MemoryAllocationLib|MdePkg/Library/PeiMemoryAllocationLib/PeiMemoryAllocationLib.inf
@@ -181,6 +182,7 @@
 
 [LibraryClasses.common.PEIM]
   PcdLib|MdePkg/Library/PeiPcdLib/PeiPcdLib.inf
+  BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
   HobLib|MdePkg/Library/PeiHobLib/PeiHobLib.inf
   PeiServicesLib|MdePkg/Library/PeiServicesLib/PeiServicesLib.inf
   MemoryAllocationLib|MdePkg/Library/PeiMemoryAllocationLib/PeiMemoryAllocationLib.inf