x11: restore default intensity to 19 on windows

x11/x11.cu

@@ -128,6 +128,15 @@ extern "C" void x11hash(void *output, const void *input)
 	memcpy(output, hash, 32);
 }
 
+/* reduce by one default intensity on windows */
+static int is_windows(void)
+{
+#ifdef WIN32
+	return 1;
+#else
+	return 0;
+#endif
+}
 
 extern "C" int scanhash_x11(int thr_id, uint32_t *pdata,
     const uint32_t *ptarget, uint32_t max_nonce,
@@ -135,7 +144,7 @@ extern "C" int scanhash_x11(int thr_id, uint32_t *pdata,
 {
 	const uint32_t first_nonce = pdata[19];
 	static bool init[8] = { 0 };
-	int intensity = (device_sm[device_map[thr_id]] >= 500) ? 20 : 19;
+	int intensity = (device_sm[device_map[thr_id]] >= 500 && !is_windows()) ? 20 : 19;
 	int throughput = opt_work_size ? opt_work_size : (1 << intensity); // 20=256*256*16;
 	throughput = min(throughput, (int)(max_nonce - first_nonce));