diff --git a/include/wx/private/display.h b/include/wx/private/display.h
index 3f74f3dc99..55ece769ed 100644
--- a/include/wx/private/display.h
+++ b/include/wx/private/display.h
@@ -115,13 +115,11 @@ public:
     // return the scale factor used to convert logical pixels to physical ones
     virtual double GetScaleFactor() const { return 1.0; }
 
-    // return the resolution of the display, uses GetSize(), GetScaleFactor()
-    // and GetSizeMM() by default but can be also overridden directly
-    virtual wxSize GetPPI() const;
+    // return the resolution of the display, by default uses GetScaleFactor(),
+    // but can be also overridden directly, as is done in wxMSW
+    virtual wxSize GetPPI() const { return wxDisplay::GetStdPPI()*GetScaleFactor(); }
 
-    // return the physical size of the display or (0, 0) if unknown: this is
-    // only used by GetPPI() implementation in the base class, so if GetPPI()
-    // is overridden, this one doesn't have to be implemented
+    // return the physical size of the display or (0, 0) if unknown
     virtual wxSize GetSizeMM() const { return wxSize(0, 0); }
 
     // return the name (may be empty)
@@ -149,11 +147,6 @@ protected:
     // create the object providing access to the display with the given index
     wxDisplayImpl(unsigned n) : m_index(n) { }
 
-    // Compute PPI from the sizes in pixels and mm.
-    //
-    // Return (0, 0) if physical size (in mm) is not known, i.e. 0.
-    static wxSize ComputePPI(int pxX, int pxY, int mmX, int mmY);
-
 
     // the index of this display (0 is always the primary one)
     const unsigned m_index;
diff --git a/src/common/dpycmn.cpp b/src/common/dpycmn.cpp
index c968f9c960..4d2feeac56 100644
--- a/src/common/dpycmn.cpp
+++ b/src/common/dpycmn.cpp
@@ -153,19 +153,7 @@ double wxDisplay::GetScaleFactor() const
 {
     wxCHECK_MSG( IsOk(), 0, wxT("invalid wxDisplay object") );
 
-#ifdef wxHAVE_DPI_INDEPENDENT_PIXELS
-    // Use wxDisplayImpl::GetScaleFactor() directly, it should be implemented
-    // correctly for the platforms doing pixel scaling and using it simpler and
-    // more efficient than using GetPPI().
     return m_impl->GetScaleFactor();
-#else
-    // Under the other platforms, we just compute the DPI ratio ourselves.
-    //
-    // We use just the vertical component of the DPI because it's the one
-    // that counts most and, in practice, it's equal to the horizontal one
-    // anyhow.
-    return m_impl->GetPPI().y / (double)GetStdPPIValue();
-#endif
 }
 
 int wxDisplay::GetDepth() const
@@ -226,35 +214,6 @@ bool wxDisplay::ChangeMode(const wxVideoMode& mode)
     return *gs_factory;
 }
 
-// ============================================================================
-// wxDisplayImpl implementation
-// ============================================================================
-
-/* static */
-wxSize wxDisplayImpl::ComputePPI(int pxX, int pxY, int mmX, int mmY)
-{
-    if ( !mmX || !mmY )
-    {
-        // Physical size is unknown, return a special value indicating that we
-        // can't compute the resolution -- what else can we do?
-        return wxSize(0, 0);
-    }
-
-    return wxSize(wxRound((pxX * inches2mm) / mmX),
-                  wxRound((pxY * inches2mm) / mmY));
-}
-
-wxSize wxDisplayImpl::GetPPI() const
-{
-    const wxSize mm = GetSizeMM();
-
-    // We need physical pixels here, not logical ones returned by
-    // GetGeometry(), to compute the real DPI.
-    const wxSize pixels = GetGeometry().GetSize()*GetScaleFactor();
-
-    return ComputePPI(pixels.x, pixels.y, mm.x, mm.y);
-}
-
 // ============================================================================
 // wxDisplayFactory implementation
 // ============================================================================
diff --git a/src/gtk/display.cpp b/src/gtk/display.cpp
index b21a0c2295..6bacd94456 100644
--- a/src/gtk/display.cpp
+++ b/src/gtk/display.cpp
@@ -255,7 +255,6 @@ public:
 #if GTK_CHECK_VERSION(3,10,0)
     virtual double GetScaleFactor() const wxOVERRIDE;
 #endif // GTK+ 3.10
-    virtual wxSize GetPPI() const wxOVERRIDE;
     virtual wxSize GetSizeMM() const wxOVERRIDE;
 
 #if wxUSE_DISPLAY
@@ -350,36 +349,6 @@ double wxDisplayImplGTK::GetScaleFactor() const
 
     return 1.0;
 }
-
-wxSize wxDisplayImplGTK::GetPPI() const
-{
-    // The useful value of PPI is the scaled value of the default PPI and not
-    // the actual PPI computed by dividing the number of pixels by the physical
-    // screen size: this is what everyone else uses, and so we should do it
-    // too.
-    return wxDisplay::GetStdPPI()*GetScaleFactor();
-}
-
-#else // GTK+ < 3.10
-
-wxSize wxDisplayImplGTK::GetPPI() const
-{
-    // Try the base class version which uses our GetSizeMM() and returns
-    // per-display PPI value if it works.
-    wxSize ppi = wxDisplayImpl::GetPPI();
-
-    if ( !ppi.x || !ppi.y )
-    {
-        // But if it didn't work, fall back to the global DPI value common to
-        // all displays -- this is still better than nothing and more
-        // compatible with the previous wxWidgets versions.
-        ppi = ComputePPI(gdk_screen_width(), gdk_screen_height(),
-                         gdk_screen_width_mm(), gdk_screen_height_mm());
-    }
-
-    return ppi;
-}
-
 #endif // GTK+ 3.10
 
 wxSize wxDisplayImplGTK::GetSizeMM() const
@@ -403,9 +372,9 @@ wxSize wxDisplayImplGTK::GetSizeMM() const
     // When we have only a single display, we can use global GTK+ functions.
     // Note that at least in some configurations, these functions return valid
     // values when gdk_screen_get_monitor_xxx_mm() only return -1, so it's
-    // always worth fallng back on them, but we can't do it when using
+    // always worth falling back on them, but we can't do it when using
     // multiple displays because they combine the sizes of all displays in this
-    // case, which would result in a completely wrong value for GetPPI().
+    // case, which would result in a completely wrong value.
     if ( !(sizeMM.x && sizeMM.y) && gdk_screen_get_n_monitors(m_screen) == 1 )
     {
         sizeMM.x = gdk_screen_width_mm();
diff --git a/src/msw/display.cpp b/src/msw/display.cpp
index 3b96ac7ab8..73ff8dd754 100644
--- a/src/msw/display.cpp
+++ b/src/msw/display.cpp
@@ -141,6 +141,7 @@ public:
     virtual wxRect GetClientArea() const wxOVERRIDE;
     virtual int GetDepth() const wxOVERRIDE;
     virtual wxSize GetPPI() const wxOVERRIDE;
+    virtual double GetScaleFactor() const wxOVERRIDE;
 
     virtual wxString GetName() const wxOVERRIDE;
     virtual bool IsPrimary() const wxOVERRIDE;
@@ -332,6 +333,12 @@ wxSize wxDisplayMSW::GetPPI() const
     return IsPrimary() ? wxDisplayImplSingleMSW().GetPPI() : wxSize(0, 0);
 }
 
+double wxDisplayMSW::GetScaleFactor() const
+{
+    const int ppi = GetPPI().y;
+    return ppi ? ppi / (double)wxDisplay::GetStdPPIValue() : 1.0;
+}
+
 wxString wxDisplayMSW::GetName() const
 {
     return m_info.monInfo.szDevice;