diff --git a/indra/llwindow/llwindow.h b/indra/llwindow/llwindow.h
index fd4efe5346..6ff41698f6 100644
--- a/indra/llwindow/llwindow.h
+++ b/indra/llwindow/llwindow.h
@@ -168,7 +168,10 @@ public:
 	virtual LLSD getNativeKeyData() { return LLSD::emptyMap(); }
 
 	// Get system UI size based on DPI (for 96 DPI UI size should be 1.0)
-	virtual F32 getSystemUISize() { return 1.0f; }
+	// <FS:Ansariel> Determine scaling of the display we show the viewer
+	//virtual F32 getSystemUISize() { return 1.0f; }
+	virtual F32 getSystemUISize(S32 x, S32 y) { return 1.0f; }
+	// </FS:Ansariel>
 
 	// <FS:TT> Window Title Access
 	//this needs to be overridden for all platforms
diff --git a/indra/llwindow/llwindowwin32.cpp b/indra/llwindow/llwindowwin32.cpp
index 1144b75257..65605a1c22 100644
--- a/indra/llwindow/llwindowwin32.cpp
+++ b/indra/llwindow/llwindowwin32.cpp
@@ -3966,7 +3966,10 @@ BOOL LLWindowWin32::handleImeRequests(WPARAM request, LPARAM param, LRESULT *res
 	return FALSE;
 }
 
-F32 LLWindowWin32::getSystemUISize()
+// <FS:Ansariel> Determine scaling of the display we show the viewer
+//F32 LLWindowWin32::getSystemUISize()
+F32 LLWindowWin32::getSystemUISize(S32 x, S32 y)
+// </FS:Ansariel>
 {
 	// <FS:Ansariel> Type fix
 	//float scale_value = 0;
@@ -3993,15 +3996,30 @@ F32 LLWindowWin32::getSystemUISize()
 			HRESULT  hr = E_FAIL;
 
 			// Get the DPI for the main monitor, and set the scaling factor
-			pt.x = 1;
-			pt.y = 1;
-			// <FS:Ansariel> Get scaling for primary display, assuming that's where we open the viewer
-			//hMonitor = MonitorFromPoint(pt, MONITOR_DEFAULTTONEAREST);
-			hMonitor = MonitorFromPoint(pt, MONITOR_DEFAULTTOPRIMARY);
+			// <FS:Ansariel> Determine scaling of the display we show the viewer
+			//pt.x = 1;
+			//pt.y = 1;
+			pt.x = x;
+			pt.y = y;
 			// </FS:Ansariel>
+			hMonitor = MonitorFromPoint(pt, MONITOR_DEFAULTTONEAREST);
 			hr = pGDFM(hMonitor, MDT_EFFECTIVE_DPI, &dpix, &dpiy);
-			scale_value = dpix / 96.0f;
+			// <FS:Ansariel> Check result before using it
+			//scale_value = dpix / 96.0f;
+			if (hr == S_OK)
+			{
+				scale_value = dpix / 96.0f;
+			}
+			else
+			{
+				LL_WARNS() << "Could not determine DPI for monitor. Defaulting to 100 %" << LL_ENDL;
+				scale_value = 1.0f;
+			}
+			// </FS:Ansariel>
 		}
+
+		// <FS:Ansariel> Free library early - not needed anymore
+		FreeLibrary(hShcore);
 	}
 	else
 	{
diff --git a/indra/llwindow/llwindowwin32.h b/indra/llwindow/llwindowwin32.h
index 15c968e82f..5d106ea79c 100644
--- a/indra/llwindow/llwindowwin32.h
+++ b/indra/llwindow/llwindowwin32.h
@@ -111,7 +111,10 @@ public:
 	/*virtual*/ void spawnWebBrowser(const std::string& escaped_url, bool async);
 				void openFile(const std::string& file_name);
 
-	/*virtual*/ F32 getSystemUISize();
+	// <FS:Ansariel> Determine scaling of the display we show the viewer
+	/*virtual*/ //F32 getSystemUISize();
+	/*virtual*/ F32 getSystemUISize(S32 x, S32 y);
+	// </FS:Ansariel>
 
 	// <FS:TT> Window Title Access
 	/*virtual*/ void setTitle(const std::string& win_title);
diff --git a/indra/newview/llviewerwindow.cpp b/indra/newview/llviewerwindow.cpp
index 2eae87250a..f19bde8216 100644
--- a/indra/newview/llviewerwindow.cpp
+++ b/indra/newview/llviewerwindow.cpp
@@ -1821,7 +1821,10 @@ LLViewerWindow::LLViewerWindow(const Params& p)
     }
 
 
-	F32 system_scale_factor = mWindow->getSystemUISize();
+	// <FS:Ansariel> Determine scaling of the display we show the viewer
+	//F32 system_scale_factor = mWindow->getSystemUISize();
+	F32 system_scale_factor = mWindow->getSystemUISize(p.x, p.y);
+	// </FS:Ansariel>
 	if (p.first_run || gSavedSettings.getF32("LastSystemUIScaleFactor") != system_scale_factor)
 	{
 		mSystemUIScaleFactorChanged = true;