diff --git a/README.md b/README.md
index 6a79bf2e..0998c0d7 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,8 @@ Discord: [Invite](https://discord.gg/XYjCGWWa4J)
 | Platform    | Support |
 | ----------- | ------- |
 | NT/XP | ❌ |
+| NT/Vista | ⚠️⚠️️ |
+| NT/Server 2008 | ⚠️⚠️ |
 | NT/Win7 | ⚠️ |
 | NT/Win8.1+ | ⚠️ |
 | NT/Win10 RS4+ | ✅ |
@@ -73,7 +75,9 @@ Discord: [Invite](https://discord.gg/XYjCGWWa4J)
 
 Win7/8: memory management (AuProcess) is limited. \
 Applications that don't need ::mmap-like functionality **with pre-reserved address allocations** should put your minimum requirements into the Vista era of NTs. \
-See: [Windows 7 defects](https://gitea.reece.sx/AuroraSupport/AuroraRuntime/src/branch/master/Media/Windows%207%20Defects.txt)
+See: [Windows 7 defects](https://gitea.reece.sx/AuroraSupport/AuroraRuntime/src/branch/master/Media/Windows%207%20Defects.txt) \
+Earlier NT revisions could be supported; however, there is creep across various subsystems and libraries for XP to not work. In addition, anything older than a fully patched Windows 7 system is untested.
+
 ## Performance
 
 Performance of each system should ideally be that of the best implementation on the platform,
diff --git a/Source/AuProcAddresses.NT.cpp b/Source/AuProcAddresses.NT.cpp
index 05948e7c..fa43f654 100644
--- a/Source/AuProcAddresses.NT.cpp
+++ b/Source/AuProcAddresses.NT.cpp
@@ -79,7 +79,8 @@ namespace Aurora
         ADD_GET_PROC(Kernel32, SetThreadInformation)
         ADD_GET_PROC(Kernel32, SetThreadSelectedCpuSets)
         ADD_GET_PROC(Kernel32, PrefetchVirtualMemory)
-            
+        ADD_GET_PROC(Kernel32, SetThreadGroupAffinity)
+
         ADD_GET_PROC(Sync, WaitOnAddress)
         ADD_GET_PROC(Sync, WakeByAddressSingle)
         ADD_GET_PROC(Sync, WakeByAddressAll)
diff --git a/Source/AuProcAddresses.NT.hpp b/Source/AuProcAddresses.NT.hpp
index 6af66216..eaf3137c 100644
--- a/Source/AuProcAddresses.NT.hpp
+++ b/Source/AuProcAddresses.NT.hpp
@@ -152,7 +152,15 @@ namespace Aurora
         const ULONG *               CpuSetIds,
         ULONG                       CpuSetIdCount
     );
-    
+
+#if defined(AURORA_PLATFORM_WIN32)
+    inline BOOL(__stdcall *pSetThreadGroupAffinity)(
+        HANDLE                      hThread,
+        GROUP_AFFINITY *            GroupAffinity,
+        PGROUP_AFFINITY             PreviousGroupAffinity
+    );
+#endif
+
     inline INT(__stdcall *pGetAddrInfoExCancel)(
         LPHANDLE                    lpHandle
     );
diff --git a/Source/Threading/Threads/AuOSThread.cpp b/Source/Threading/Threads/AuOSThread.cpp
index 72253f67..c236922b 100644
--- a/Source/Threading/Threads/AuOSThread.cpp
+++ b/Source/Threading/Threads/AuOSThread.cpp
@@ -980,12 +980,17 @@ namespace Aurora::Threading::Threads
         }
 
     #if defined(AURORA_PLATFORM_WIN32)
-        GROUP_AFFINITY affinityGroup {0};
-        mask.ToMsWin7GroupAffinity(&affinityGroup);
-        if (SetThreadGroupAffinity(this->handle_, &affinityGroup, nullptr))
+        if (pSetThreadGroupAffinity)
         {
-            return;
+            GROUP_AFFINITY affinityGroup { 0 };
+            mask.ToMsWin7GroupAffinity(&affinityGroup);
+            if (pSetThreadGroupAffinity(this->handle_, &affinityGroup, nullptr))
+            {
+                return;
+            }
         }
+
+        SetThreadAffinityMask(this->handle_, mask.lower);
     #endif
 
         SysPushErrorUnavailableError("Couldn't set thread affinity");