1 files changed, 9 insertions, 1 deletions
diff --git a/indra/llwindow/llwindowmacosx.cpp b/indra/llwindow/llwindowmacosx.cpp
index c29131d60b..922fa745bd 100644
--- a/indra/llwindow/llwindowmacosx.cpp
+++ b/indra/llwindow/llwindowmacosx.cpp
@@ -49,6 +49,8 @@ BOOL gHiDPISupport = TRUE;
 const S32	BITS_PER_PIXEL = 32;
 const S32	MAX_NUM_RESOLUTIONS = 32;
 
+const S32   DEFAULT_REFRESH_RATE = 60;
+
 namespace
 {
     NSKeyEventRef mRawKeyEvent = NULL;
@@ -634,7 +636,6 @@ BOOL LLWindowMacOSX::createContext(int x, int y, int width, int height, int bits
 		// Get the view instead.
 		mGLView = createOpenGLView(mWindow, mFSAASamples, enable_vsync);
 		mContext = getCGLContextObj(mGLView);
-		
 		gGLManager.mVRAM = getVramSize(mGLView);
 	}
 	
@@ -655,6 +656,13 @@ BOOL LLWindowMacOSX::createContext(int x, int y, int width, int height, int bits
 		}
 	}
 
+    mRefreshRate = CGDisplayModeGetRefreshRate(CGDisplayCopyDisplayMode(mDisplay));
+    if(mRefreshRate == 0)
+    {
+        //consider adding more appropriate fallback later
+        mRefreshRate = DEFAULT_REFRESH_RATE;
+    }
+
 	// Disable vertical sync for swap
     toggleVSync(enable_vsync);