Ticket #4572: ScreenPrefFix.diff

screen/ScreenMode.cpp

@@ -328 +328 @@
             + info.height * info.height) / 0.254) / 10.0;
     }
 
+    // Some older CRT monitors do not contain the monitor range information
+    // (EDID1_MONITOR_RANGES) in their EDID info resulting in the min/max
+    // horizontal/vertical frequencies being zero.  In this case, set the
+    // vertical frequency range to 60..85 Hz.
+
+    if (info.min_vertical_frequency == 0) {
+        info.min_vertical_frequency = 60;
+        info.max_vertical_frequency = 85;
+    }
+
     // TODO: If the names aren't sound, we could see if we find/create a
     // database for the entries with user presentable names; they are fine
     // for the models I could test with so far.