diff --git a/Misc/NEWS.d/next/Windows/2019-09-11-14-51-56.bpo-32592.jvQMD9.rst b/Misc/NEWS.d/next/Windows/2019-09-11-14-51-56.bpo-32592.jvQMD9.rst
new file mode 100644
index 0000000..c07a121
--- /dev/null
+++ b/Misc/NEWS.d/next/Windows/2019-09-11-14-51-56.bpo-32592.jvQMD9.rst
@@ -0,0 +1 @@
+Set Windows 8 as the minimum required version for API support
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 089572f..e71d4b2 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -12204,8 +12204,6 @@
 {
     int ncpu = 0;
 #ifdef MS_WINDOWS
-    /* Declare prototype here to avoid pulling in all of the Win7 APIs in 3.8 */
-    DWORD WINAPI GetActiveProcessorCount(WORD group);
     ncpu = GetActiveProcessorCount(ALL_PROCESSOR_GROUPS);
 #elif defined(__hpux)
     ncpu = mpctl(MPC_GETNUMSPUS, NULL, NULL);
diff --git a/PC/pyconfig.h b/PC/pyconfig.h
index 9304c72..d407e1d 100644
--- a/PC/pyconfig.h
+++ b/PC/pyconfig.h
@@ -135,9 +135,9 @@
 #endif /* MS_WIN64 */
 
 /* set the version macros for the windows headers */
-/* Python 3.5+ requires Windows Vista or greater */
-#define Py_WINVER 0x0600 /* _WIN32_WINNT_VISTA */
-#define Py_NTDDI NTDDI_VISTA
+/* Python 3.9+ requires Windows 8 or greater */
+#define Py_WINVER 0x0602 /* _WIN32_WINNT_WIN8 */
+#define Py_NTDDI NTDDI_WIN8
 
 /* We only set these values when building Python - we don't want to force
    these values on extensions, as that will affect the prototypes and