diff --git a/intern/cycles/render/osl.cpp b/intern/cycles/render/osl.cpp
index 6bff29d1c76..a794f233718 100644
--- a/intern/cycles/render/osl.cpp
+++ b/intern/cycles/render/osl.cpp
@@ -156,6 +156,7 @@ void OSLShaderManager::device_free(Device *device, DeviceScene *dscene, Scene *s
 	og->surface_state.clear();
 	og->volume_state.clear();
 	og->displacement_state.clear();
+	og->bump_state.clear();
 	og->background_state.reset();
 }
 
diff --git a/intern/ghost/intern/GHOST_SystemWin32.cpp b/intern/ghost/intern/GHOST_SystemWin32.cpp
index 9f03b5e9537..b0dae432643 100644
--- a/intern/ghost/intern/GHOST_SystemWin32.cpp
+++ b/intern/ghost/intern/GHOST_SystemWin32.cpp
@@ -941,6 +941,8 @@ LRESULT WINAPI GHOST_SystemWin32::s_wndProc(HWND hwnd, UINT msg, WPARAM wParam,
 	GHOST_ASSERT(system, "GHOST_SystemWin32::s_wndProc(): system not initialized");
 
 	if (hwnd) {
+#if 0
+		// Disabled due to bug in Intel drivers, see T51959
 		if(msg == WM_NCCREATE) {
 			// Tell Windows to automatically handle scaling of non-client areas
 			// such as the caption bar. EnableNonClientDpiScaling was introduced in Windows 10
@@ -954,6 +956,7 @@ LRESULT WINAPI GHOST_SystemWin32::s_wndProc(HWND hwnd, UINT msg, WPARAM wParam,
 				}
 			}
 		}
+#endif
 
 		GHOST_WindowWin32 *window = (GHOST_WindowWin32 *)::GetWindowLongPtr(hwnd, GWLP_USERDATA);
 		if (window) {