Some Win64 pre-release in 2000 didn't support
QueryPerformanceCounter(), but we believe Win64 does
support it now.  So use in time.clock().

It would be peachy if someone with a Win64 box tried
this ;-)
diff --git a/Modules/timemodule.c b/Modules/timemodule.c
index 742d6bf..eb9f4d0 100644
--- a/Modules/timemodule.c
+++ b/Modules/timemodule.c
@@ -63,11 +63,10 @@
 #endif /* MS_WINDOWS */
 #endif /* !__WATCOMC__ || __QNX__ */
 
-#if defined(MS_WINDOWS) && !defined(MS_WIN64) && !defined(__BORLANDC__)
+#if defined(MS_WINDOWS) && !defined(__BORLANDC__)
 /* Win32 has better clock replacement
-   XXX Win64 does not yet, but might when the platform matures. */
 #undef HAVE_CLOCK /* We have our own version down below */
-#endif /* MS_WINDOWS && !MS_WIN64 */
+#endif /* MS_WINDOWS && !defined(__BORLANDC__) */
 
 #if defined(PYOS_OS2)
 #define INCL_DOS
@@ -821,7 +820,7 @@
 	SetConsoleCtrlHandler( PyCtrlHandler, TRUE);
 #endif /* MS_WINDOWS */
 	if (!initialized) {
-		PyStructSequence_InitType(&StructTimeType, 
+		PyStructSequence_InitType(&StructTimeType,
 					  &struct_time_type_desc);
 	}
 	Py_INCREF(&StructTimeType);